A healthy diet is one that helps to maintain or improve overall health. A healthy diet provides the body with essential nutrition: fluid, adequate amino acids from protein, essential fatty acids, vitamins, minerals, fibre and adequate calories.
The requirements for a healthy diet can be met from a variety of plant-based and animal-based foods, although a non-animal source of vitamin B12 is needed for those following a vegan diet. A healthy diet supports energy needs and provides for human nutrition without exposure to toxicity or excessive weight gain from consuming more calories than the body requires. A healthy diet, in addition to exercise, is thought to be important for lowering health risks, such as obesity, heart disease, type 2 diabetes, hypertension and cancer.
Various nutrition guides are published by medical and governmental institutions to educate individuals on what they should be eating to promote health. Nutrition facts labels are also mandatory in some countries to allow consumers to choose between foods based on the components relevant to health.
The idea of dietary therapy (using dietary choices to maintain health and improve poor health) is quite old and thus has both modern scientific forms (medical nutrition therapy) and prescientific forms (such as dietary therapy in traditional Chinese medicine).
World Health Organization
The World Health Organization (WHO) makes the following 5 recommendations with respect to both populations and individuals:
- Maintain a healthy weight by eating roughly the same number of calories that your body is using.
- Limit intake of fats. Not more than 30% of the total calories should come from fats. Prefer unsaturated fats to saturated fats. Avoid trans fats.
- Eat at least 400 grams of fruits and vegetables per day (potatoes, sweet potatoes, cassava and other starchy roots do not count). A healthy diet also contains legumes (e.g. lentils, beans), whole grains and nuts.
- Limit the intake of simple sugars to less than 10% of calorie (below 5% of calories or 25 grams may be even better)
- Limit salt / sodium from all sources and ensure that salt is iodized. Less than 5 grams of salt per day can reduce the risk of cardiovascular disease.
WHO stated that insufficient vegetables and fruit is the cause of 2.8% of deaths worldwide.
Other WHO recommendations include ensuring that foods chosen have sufficient vitamins and certain minerals, avoiding directly poisonous (e.g. heavy metals) and carcinogenic (e.g. benzene) substances, avoiding foods contaminated by human pathogens (e.g. E. coli, tapeworm eggs), and replacing saturated fats with polyunsaturated fats in the diet can reduce the risk of coronary artery disease and diabetes.
United States Department of Agriculture
Main article: History of USDA nutrition guides
Main article: MyPlate
The Dietary Guidelines for Americans by the United States Department of Agriculture (USDA) recommends three healthy patterns of diet, summarized in table below, for a 2000 kcal diet.
It emphasizes both health and environmental sustainability and a flexible approach: the committee that drafted it wrote: "The major findings regarding sustainable diets were that a diet higher in plant-based foods, such as vegetables, fruits, whole grains, legumes, nuts, and seeds, and lower in calories and animal-based foods is more health promoting and is associated with less environmental impact than is the current U.S. diet. This pattern of eating can be achieved through a variety of dietary patterns, including the “Healthy U.S.-style Pattern,” the “Healthy Vegetarian Pattern," and the "Healthy Mediterranean-style Pattern". Food group amounts are per day, unless noted per week.
|Food group/subgroup (units)||Healthy U.S. patterns||Healthy Vegetarian patterns||Healthy Med-style patterns|
|Fruits (cup eq)||2||2||2.5|
|Vegetables (cup eq)||2.5||2.5||2.5|
|Grains (oz eq)||6||6.5||6|
|Dairy (cup eq)||3||3||2|
|Protein Foods (oz eq)||5.5||3.5||6.5|
|Meat (red and processed)||12.5/wk||--||12.5/wk|
|Processed Soy (including tofu)||0.5/wk||8/wk||0.5/wk|
|Solid fats limit (grams)||18||21||17|
|Added sugars limit (grams)||30||36||29|
American Heart Association / World Cancer Research Fund / American Institute for Cancer Research
The American Heart Association, World Cancer Research Fund, and American Institute for Cancer Research recommend a diet that consists mostly of unprocessed plant foods, with emphasis a wide range of whole grains, legumes, and non-starchy vegetables and fruits. This healthy diet is full of a wide range of various non-starchy vegetables and fruits, that provide different colors including red, green, yellow, white, purple, and orange. They note that tomato cooked with oil, allium vegetables like garlic, and cruciferous vegetables like cauliflower, provide some protection against cancer. This healthy diet is low in energy density, which may protect against weight gain and associated diseases. Finally, limiting consumption of sugary drinks, limiting energy rich foods, including “fast foods” and red meat, and avoiding processed meats improves health and longevity. Overall, researchers and medical policy conclude that this healthy diet can reduce the risk of chronic disease and cancer.
In children, consuming less than 25 grams of added sugar (100 calories) is recommended per day. Other recommendations include no extra sugars in those under 2 years old and less than one soft drink per week. As of 2017, decreasing total fat is no longer recommended, but instead, the recommendation to lower risk of cardiovascular disease is to increase consumption of monounsaturated fats and polyunsaturated fats, while decreasing consumption of saturated fats.
Harvard School of Public Health
Further information: Healthy eating pyramid
The Nutrition Source of Harvard School of Public Health makes the following 10 recommendations for a healthy diet:
- Choose good carbohydrates: whole grains (the less processed the better), vegetables, fruits and beans. Avoid white bread, white rice, and the like as well as pastries, sugared sodas, and other highly processed food.
- Pay attention to the protein package: good choices include fish, poultry, nuts, and beans. Try to avoid red meat.
- Choose foods containing healthy fats. Plant oils, nuts, and fish are the best choices. Limit consumption of saturated fats, and avoid foods with trans fat.
- Choose a fiber-filled diet which includes whole grains, vegetables, and fruits.
- Eat more vegetables and fruits—the more colorful and varied, the better.
- Include adequate amounts of calcium in the diet; however, milk is not the best or only source. Good sources of calcium are collards, bok choy, fortified soy milk, baked beans, and supplements containing calcium and vitamin D.
- Prefer water over other beverages. Avoid sugary drinks, and limit intake of juices and milk. Coffee, tea, artificially-sweetened drinks, 100-percent fruit juices, low-fat milk and alcohol can fit into a healthy diet but are best consumed in moderation. Sports drinks are recommended only for people who exercise more than an hour at a stretch to replace substances lost in sweat.
- Limit salt intake. Choose more fresh foods, instead of processed ones.
- Drink alcohol in moderation. Doing so has health benefits, but is not recommended for everyone.
- Consider intake of daily multivitamin and extra vitamin D, as these have potential health benefits.
Other than nutrition, the guide recommends frequent physical exercise and maintaining a healthy body weight.
David L. Katz, who reviewed the most prevalent popular diets in 2014, noted:
The weight of evidence strongly supports a theme of healthful eating while allowing for variations on that theme. A diet of minimally processed foods close to nature, predominantly plants, is decisively associated with health promotion and disease prevention and is consistent with the salient components of seemingly distinct dietary approaches. Efforts to improve public health through diet are forestalled not for want of knowledge about the optimal feeding of Homo sapiens but for distractions associated with exaggerated claims, and our failure to convert what we reliably know into what we routinely do. Knowledge in this case is not, as of yet, power; would that it were so.
Marion Nestle expresses the mainstream view among scientists who study nutrition::10
The basic principles of good diets are so simple that I can summarize them in just ten words: eat less, move more, eat lots of fruits and vegetables. For additional clarification, a five-word modifier helps: go easy on junk foods. Follow these precepts and you will go a long way toward preventing the major diseases of our overfed society—coronary heart disease, certain cancers, diabetes, stroke, osteoporosis, and a host of others.... These precepts constitute the bottom line of what seem to be the far more complicated dietary recommendations of many health organizations and national and international governments—the forty-one “key recommendations” of the 2005 Dietary Guidelines, for example. ... Although you may feel as though advice about nutrition is constantly changing, the basic ideas behind my four precepts have not changed in half a century. And they leave plenty of room for enjoying the pleasures of food.:22
For specific conditions
In addition to dietary recommendations for the general population, there are many specific diets that have primarily been developed to promote better health in specific population groups, such as people with high blood pressure (as in low sodium diets or the more specific DASH diet), or people who are overweight or obese (in weight control diets). However, some of them may have more or less evidence for beneficial effects in normal people as well.
A low sodium diet is beneficial for people with high blood pressure. A Cochrane review published in 2008 concluded that a long term (more than 4 weeks) low sodium diet has a useful effect to reduce blood pressure, both in people with hypertension and in people with normal blood pressure.
The DASH diet (Dietary Approaches to Stop Hypertension) is a diet promoted by the National Heart, Lung, and Blood Institute (part of the NIH, a United States government organization) to control hypertension. A major feature of the plan is limiting intake of sodium, and the diet also generally encourages the consumption of nuts, whole grains, fish, poultry, fruits, and vegetables while lowering the consumption of red meats, sweets, and sugar. It is also "rich in potassium, magnesium, and calcium, as well as protein".
The Mediterranean diet, which includes limiting consumption of red meat and using olive oil in cooking, has also been shown to improve cardiovascular outcomes.
Further information: Dieting
Weight control diets aim to maintain a controlled weight. In most cases, those who are overweight or obese use dieting in combination with physical exercise to lose weight.
Diets to promote weight loss are divided into four categories: low-fat, low-carbohydrate, low-calorie, and very low calorie. A meta-analysis of six randomized controlled trials found no difference between the main diet types (low calorie, low carbohydrate, and low fat), with a 2–4 kilogram weight loss in all studies. At two years, all calorie-reduced diet types cause equal weight loss regardless of the macronutrients emphasized.
Reduced disease risk
Further information: Diet and cancer
There may be a relationship between lifestyle including food consumption and potentially lowering the risk of cancer or other chronic diseases. A diet high in fruits and vegetables appears to decrease the risk of cardiovascular disease and death but not cancer.
A healthy diet may consist mostly of whole plant foods, with limited consumption of energy dense foods, red meat, alcoholic drinks and salt while reducing consumption of sugary drinks, and processed meat. A healthy diet may contain non-starchy vegetables and fruits, including those with red, green, yellow, white, purple or orange pigments. Tomato cooked with oil, allium vegetables like garlic, and cruciferous vegetables like cauliflower "probably" contain compounds which are under research for their possible anti-cancer activity.
A healthy diet is low in energy density, lowering caloric content, thereby possibly inhibiting weight gain and lowering risk against chronic diseases. Chronic Western diseases are associated with pathologically increased IGF-1 levels. Findings in molecular biology and epidemiologic data suggest that milk consumption is a promoter of chronic diseases of Western nations, including atherosclerosis, carcinogenesis and neurodegenerative diseases.
The Western pattern diet which is typically eaten by Americans and increasingly adapted by people in the developing world as they leave poverty is unhealthy: it is "rich in red meat, dairy products, processed and artificially sweetened foods, and salt, with minimal intake of fruits, vegetables, fish, legumes, and whole grains."
An unhealthy diet is a major risk factor for a number of chronic diseases including: high blood pressure, diabetes, abnormal blood lipids, overweight/obesity, cardiovascular diseases, and cancer.
The WHO estimates that 2.7 million deaths are attributable to a diet low in fruits and vegetables every year. Globally it is estimated to cause about 19% of gastrointestinal cancer, 31% of ischaemic heart disease, and 11% of strokes, thus making it one of the leading preventable causes of death worldwide.
Popular diets, often referred to as fad diets, make promises of weight loss or other health advantages such as longer life without backing by solid science, and in many cases are characterized by highly restrictive or unusual food choices.:296 Celebrity endorsements (including celebrity doctors) are frequently associated with popular diets, and the individuals who develop and promote these programs often profit handsomely.:11–12
Fears of high cholesterol were frequently voiced up until the mid-1990s. However, more recent research has shown that the distinction between high- and low-density lipoprotein ('good' and 'bad' cholesterol, respectively) must be addressed when speaking of the potential ill effects of cholesterol. Different types of dietary fat have different effects on blood levels of cholesterol. For example, polyunsaturated fats tend to decrease both types of cholesterol; monounsaturated fats tend to lower LDL and raise HDL; saturated fats tend to either raise HDL, or raise both HDL and LDL; and trans fat tend to raise LDL and lower HDL.
While dietary cholesterol is only found in animal products such as meat, eggs, and dairy, studies have not found a link between eating cholesterol and blood levels of cholesterol.
Vending machines in particular have come under fire as being avenues of entry into schools for junk food promoters. However, there is little in the way of regulation and it is difficult for most people to properly analyze the real merits of a company referring to itself as "healthy." Recently, the Committee of Advertising Practice in the United Kingdom launched a proposal to limit media advertising for food and soft drink products high in fat, salt or sugar. The British Heart Foundation released its own government-funded advertisements, labeled "Food4Thought", which were targeted at children and adults to discourage unhealthy habits of consuming junk food.
From a psychological and cultural perspective, a healthier diet may be difficult to achieve for people with poor eating habits. This may be due to tastes acquired in childhood and preferences for sugary, salty and/or fatty foods.
Animals that are kept by humans also benefit from a healthy diet and the requirements of such diets may be very different from the ideal human diet.
- ^"Essential Amino Acid Requirements: A Review".
- ^Melina, Vesanto; Craig, Winston; Levin, Susan (December 2016). "Position of the Academy of Nutrition and Dietetics: Vegetarian Diets". Journal of the Academy of Nutrition and Dietetics. 116 (12): 1970–1980. doi:10.1016/j.jand.2016.09.025.
- ^ ab"WHO | Promoting fruit and vegetable consumption around the world". WHO.
- ^"Food information to consumers - legislation". EU. Retrieved 2017-11-24.
- ^"WHO | Diet". WHO.
- ^"WHO guideline : sugar consumption recommendation". World Health Organization. Retrieved 6 January 2018.
- ^ abc"WHO - Unhealthy diet". who.int.
- ^Dietary Guidelines Advisory Committee. "Scientific Report of the 2015 Dietary Guidelines Advisory Committee." Washington (DC): USDA and US Department of Health and Human Services (2015).
- ^"App. E-3.7: Developing Vegetarian and Mediterranean-style Food Patterns - 2015 Advisory Report - health.gov". health.gov. Retrieved 2015-09-30.
- ^ abc"Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective"(PDF). Washington DC: AICR, 2007. ISBN 978-0-9722522-2-5.
- ^ abc"American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer Prevention"(PDF). Last Revised: 1/11/2012.
- ^ abVos, Miriam B.; Kaar, Jill L.; Welsh, Jean A.; Van Horn, Linda V.; Feig, Daniel I.; Anderson, Cheryl A.M.; Patel, Mahesh J.; Cruz Munos, Jessica; Krebs, Nancy F.; Xanthakos, Stavra A.; Johnson, Rachel K. (22 August 2016). "Added Sugars and Cardiovascular Disease Risk in Children". Circulation: CIR.0000000000000439. doi:10.1161/CIR.0000000000000439. PMID 27550974.
- ^Sacks, Frank M.; Lichtenstein, Alice H.; Wu, Jason H.Y.; Appel, Lawrence J.; Creager, Mark A.; Kris-Etherton, Penny M.; Miller, Michael; Rimm, Eric B.; Rudel, Lawrence L.; Robinson, Jennifer G.; Stone, Neil J.; Van Horn, Linda V. (15 June 2017). "Dietary Fats and Cardiovascular Disease: A Presidential Advisory From the American Heart Association"(PDF). Circulation: CIR.0000000000000510. doi:10.1161/CIR.0000000000000510.
- ^ abcdefg"What Should I Eat?". The Nutrition Source. Harvard School of Public Health. Archived from the original on 1 August 2012. Retrieved 17 October 2012.
- ^"Carbohydrates". Archived from the original on 2011-07-07.
- ^"Protein: Moving Closer to Center Stage". Retrieved October 1, 2014.
- ^"The Bottom Line: Choose a fiber-filled diet, rich in whole grains, vegetables, and fruits". Retrieved October 27, 2012.
- ^"The Bottom Line: Calcium is important. But milk isn't the only, or even best, source". Archived from the original on October 24, 2012. Retrieved October 27, 2012.
- ^"The Nutrition Source Healthy Beverage Guidelines". Retrieved October 27, 2012.
- ^Katz DL, Meller S (2014). "Can we say what diet is best for health?". Annu Rev Public Health. 35: 83–103. doi:10.1146/annurev-publhealth-032013-182351. PMID 24641555.
- ^ abFitzgerald M (2014). Diet Cults: The Surprising Fallacy at the Core of Nutrition Fads and a Guide to Healthy Eating for the Rest of US. Pegasus Books. ISBN 978-1-60598-560-2.
- ^ abNestle, Marion (2006). What to Eat. New York: North Point Press (Farrar, Straus and Giroux). p. 611. ISBN 978-0-86547-738-4.
- ^He FJ, MacGregor GA (2004). "Effect of longer-term modest salt reduction on blood pressure". Cochrane Database of Systematic Reviews. 1: CD004937. doi:10.1002/14651858.CD004937. PMID 15266549.
- ^"Your Guide To Lowering Your Blood Pressure With DASH"(PDF). Retrieved 2009-06-08.
- ^Walker C, Reamy BV (April 2009). "Diets for cardiovascular disease prevention: what is the evidence?". Am Fam Physician. 79 (7): 571–7. PMID 19378874.
- ^ abStrychar I (January 2006). "Diet in the management of weight loss". CMAJ. 174 (1): 56–63. doi:10.1503/cmaj.045037. PMC 1319349. PMID 16389240.
- ^Sacks FM, Bray GA, Carey VJ, et al. (February 2009). "Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates". N. Engl. J. Med. 360 (9): 859–73. doi:10.1056/NEJMoa0804748. PMC 2763382. PMID 19246357.
- ^Wang, X; Ouyang, Y; Liu, J; Zhu, M; Zhao, G; Bao, W; Hu, FB (Jul 29, 2014). "Fruit and vegetable consumption and mortality from all causes, cardiovascular disease, and cancer: systematic review and dose-response meta-analysis of prospective cohort studies". BMJ (Clinical research ed.). 349: g4490. doi:10.1136/bmj.g4490. PMC 4115152. PMID 25073782.
- ^Executive Summary: Policy and Action for Cancer Prevention Food, Nutrition, and Physical Activity(PDF). World Cancer Research Fund. 2010. p. 1. ISBN 978-0-9722522-5-6.
- ^"Cancer Trends Progress Report - Fruit and Vegetable Consumption". Archived from the original on 2012-12-16. Retrieved 2012-07-14.
- ^Melnik B. (Apr 2009). "Milk consumption: aggravating factor of acne and promoter of chronic diseases of Western societies". J Dtsch Dermatol Ges. 7 (4): 364–70. doi:10.1111/j.1610-0387.2009.07019.x. PMID 19243483.
- ^Bloomfield, HE; Kane, R; Koeller, E; Greer, N; MacDonald, R; Wilt, T (November 2015). "Benefits and Harms of the Mediterranean Diet Compared to Other Diets"(PDF). VA Evidence-based Synthesis Program Reports. PMID 27559560.
- ^ ab"WHO | Diet and physical activity: a public health priority".
- ^Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJ (May 2006). "Global and regional burden of disease and risk factors, 2001: systematic analysis of population health data". Lancet. 367 (9524): 1747–57. doi:10.1016/S0140-6736(06)68770-9. PMID 16731270.
- ^Jennifer Robbins, Silvina Pugliese, Diana Cullum-Dugan, Carine Lenders, Kathy Gorman Ireland Popular Diets Page accessed Jan 28, 2016
- ^Tina Gianoulis, "Dieting" in the St. James Encyclopedia of Popular Culture Ed. Thomas Riggs. Vol. 2. 2nd ed. Detroit: St. James Press, 2013. p106-108. ISBN 978-1-55862-847-2
- ^Mensink RP, Zock PL, Kester AD, Katan MB (May 2003). "Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials". American Journal of Clinical Nutrition. 77 (5): 1146–1155. ISSN 0002-9165. PMID 12716665.
- ^Thijssen, M.A. and R.P. Mensink. (2005). Fatty Acids and Atherosclerotic Risk. In Arnold von Eckardstein (Ed.) Atherosclerosis: Diet and Drugs. Springer. pp. 171–172. ISBN 978-3-540-22569-0.
- ^"Part D. Chapter 1: Food and Nutrient Intakes, and Health: Current Status and Trends - Continued". Office of Disease Prevention and Health Promotion. 2015. Retrieved 12 May 2015.
- ^"Launch of public consultation on new food ad rules". Committee of Advertising Practice. 2016. Retrieved 16 August 2016.
- ^"British Heart Foundation launches Food4Thought campaign". British Cardiovascular Society. 22 September 2006. Retrieved 16 August 2016.
- ^"Told to Eat Its Vegetables, America Orders Fries" article by Kim Severson in The New York Times September 24, 2010, accessed September 25, 2010
- ^James WP (2008). "The fundamental drivers of the obesity epidemic". Obesity Research. 9 Suppl 1 (Mar;9 Suppl 1:6-13): 6–13. doi:10.1111/j.1467-789X.2007.00432.x. PMID 18307693.
- ^"Heathlthy and Balanced Diet for Dogs". RSPCA. 2017. Retrieved 8 December 2017.
This article is about the human condition. For other uses, see Health (disambiguation).
"Healthy Living" redirects here. For the publishing imprint, see Book Publishing Company.
Health is the level of functional and metabolic efficiency of a living organism. The World Health Organization (WHO) defined human health in its broader sense in its 1948 constitution as "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity." This definition has been subject to controversy, in particular as lacking operational value, the ambiguity in developing cohesive health strategies, and because of the problem created by use of the word "complete", which makes it practically impossible to achieve. Other definitions have been proposed, among which a recent definition that correlates health and personal satisfaction.
An alternative approach focuses on avoiding definitions, which demand precise descriptions of the term. Instead, following a three-year global conversation, convened by Alex Jadad, "health" has been conceptualized as the ability to adapt and self manage when individuals communities face physical, mental or social challenges.
The definition of health has evolved over time. In keeping with the biomedical perspective, early definitions of health focused on the theme of the body's ability to function; health was seen as a state of normal function that could be disrupted from time to time by disease. An example of such a definition of health is: "a state characterized by anatomic, physiologic, and psychological integrity; ability to perform personally valued family, work, and community roles; ability to deal with physical, biological, psychological, and social stress". Then, in 1948, in a radical departure from previous definitions, the World Health Organization (WHO) proposed a definition that aimed higher: linking health to well-being, in terms of "physical, mental, and social well-being, and not merely the absence of disease and infirmity". Although this definition was welcomed by some as being innovative, it was also criticized as being vague, excessively broad, and was not construed as measurable. For a long time, it was set aside as an impractical ideal and most discussions of health returned to the practicality of the biomedical model.
Just as there was a shift from viewing disease as a state to thinking of it as a process, the same shift happened in definitions of health. Again, the WHO played a leading role when it fostered the development of the health promotion movement in the 1980s. This brought in a new conception of health, not as a state, but in dynamic terms of resiliency, in other words, as "a resource for living". 1984 WHO revised the definition of health defined it as "the extent to which an individual or group is able to realize aspirations and satisfy needs and to change or cope with the environment. Health is a resource for everyday life, not the objective of living; it is a positive concept, emphasizing social and personal resources, as well as physical capacities". Thus, health referred to the ability to maintain homeostasis and recover from insults. Mental, intellectual, emotional, and social health referred to a person's ability to handle stress, to acquire skills, to maintain relationships, all of which form resources for resiliency and independent living.
Since the late 1970s, the federal Healthy People Initiative has been a visible component of the United States’ approach to improving population health. In each decade, a new version of Healthy People is issued, featuring updated goals and identifying topic areas and quantifiable objectives for health improvement during the succeeding ten years, with assessment at that point of progress or lack thereof. Progress has been limited to many objectives, leading to concerns about the effectiveness of Healthy People in shaping outcomes in the context of a decentralized and uncoordinated US health system. Healthy People 2020 gives more prominence to health promotion and preventive approaches and adds a substantive focus on the importance of addressing social determinants of health. A new expanded digital interface facilitates use and dissemination rather than bulky printed books as produced in the past. The impact of these changes to Healthy People will be determined in the coming years.
Systematic activities to prevent or cure health problems and promote good health in humans are undertaken by health care providers. Applications with regard to animal health are covered by the veterinary sciences. The term "healthy" is also widely used in the context of many types of non-living organizations and their impacts for the benefit of humans, such as in the sense of healthy communities, healthy cities or healthy environments. In addition to health care interventions and a person's surroundings, a number of other factors are known to influence the health status of individuals, including their background, lifestyle, and economic, social conditions, and spirituality; these are referred to as "determinants of health." Studies have shown that high levels of stress can affect human health.
In the first decade of the 21th century, the conceptualization of health as an ability opened the door for self-assessments to become the main indicators to judge the performance of efforts aimed at improving human health. It also created the opportunity for every person to feel healthy, even in the presence of multiple chronic diseases, or a terminal condition, and for the re-examination of determinants of health, away from the traditional approach that focuses on the reduction of the prevalence of diseases.
See also: Social determinants of health and Risk factor
Generally, the context in which an individual lives is of great importance for both his health status and quality of their life. It is increasingly recognized that health is maintained and improved not only through the advancement and application of health science, but also through the efforts and intelligent lifestyle choices of the individual and society. According to the World Health Organization, the main determinants of health include the social and economic environment, the physical environment, and the person's individual characteristics and behaviors.
More specifically, key factors that have been found to influence whether people are healthy or unhealthy include the following:
An increasing number of studies and reports from different organizations and contexts examine the linkages between health and different factors, including lifestyles, environments, health care organization, and health policy, one specific health policy brought into many countries in recent years was the introduction of the sugar tax. Beverage taxes came into light with increasing concerns about obesity, particularly among youth. Sugar-sweetened beverages have become a target of anti-obesity initiatives with increasing evidence of their link to obesity.– such as the 1974 Lalonde report from Canada; the Alameda County Study in California; and the series of World Health Reports of the World Health Organization, which focuses on global health issues including access to health care and improving public health outcomes, especially in developing countries.
The concept of the "health field," as distinct from medical care, emerged from the Lalonde report from Canada. The report identified three interdependent fields as key determinants of an individual's health. These are:
- Lifestyle: the aggregation of personal decisions (i.e., over which the individual has control) that can be said to contribute to, or cause, illness or death;
- Environmental: all matters related to health external to the human body and over which the individual has little or no control;
- Biomedical: all aspects of health, physical and mental, developed within the human body as influenced by genetic make-up.
The maintenance and promotion of health is achieved through different combination of physical, mental, and social well-being, together sometimes referred to as the "health triangle." The WHO's 1986 Ottawa Charter for Health Promotion further stated that health is not just a state, but also "a resource for everyday life, not the objective of living. Health is a positive concept emphasizing social and personal resources, as well as physical capacities."
Focusing more on lifestyle issues and their relationships with functional health, data from the Alameda County Study suggested that people can improve their health via exercise, enough sleep, maintaining a healthy body weight, limiting alcohol use, and avoiding smoking. Health and illness can co-exist, as even people with multiple chronic diseases or terminal illnesses can consider themselves healthy.
The environment is often cited as an important factor influencing the health status of individuals. This includes characteristics of the natural environment, the built environment, and the social environment. Factors such as clean water and air, adequate housing, and safe communities and roads all have been found to contribute to good health, especially to the health of infants and children. Some studies have shown that a lack of neighborhood recreational spaces including natural environment leads to lower levels of personal satisfaction and higher levels of obesity, linked to lower overall health and well being. This suggests that the positive health benefits of natural space in urban neighborhoods should be taken into account in public policy and land use.
Genetics, or inherited traits from parents, also play a role in determining the health status of individuals and populations. This can encompass both the predisposition to certain diseases and health conditions, as well as the habits and behaviors individuals develop through the lifestyle of their families. For example, genetics may play a role in the manner in which people cope with stress, either mental, emotional or physical. For example, obesity is a significant problem in the United States that contributes to bad mental health and causes stress in the lives of great numbers of people. (One difficulty is the issue raised by the debate over the relative strengths of genetics and other factors; interactions between genetics and environment may be of particular importance.)
A number of types of health issues are common around the globe. Disease is one of the most common. According to GlobalIssues.org, approximately 36 million people die each year from non-communicable (not contagious) disease including cardiovascular disease, cancer, diabetes and chronic lung disease (Shah, 2014).
Among communicable diseases, both viral and bacterial, AIDS/HIV, tuberculosis, and malaria are the most common, causing millions of deaths every year (2014).
Another health issue that causes death or contributes to other health problems is malnutrition, especially among children. One of the groups malnutrition affects most is young children. Approximately 7.5 million children under the age of 5 die from malnutrition, usually brought on by not having the money to find or make food (2014).
Bodily injuries are also a common health issue worldwide. These injuries, including broken bones, fractures, and burns can reduce a person's quality of life or can cause fatalities including infections that resulted from the injury or the severity injury in general (Moffett, 2013).
Lifestyle choices are contributing factors to poor health in many cases. These include smoking cigarettes, and can also include a poor diet, whether it is overeating or an overly constrictive diet. Inactivity can also contribute to health issues and also a lack of sleep, excessive alcohol consumption, and neglect of oral hygiene (2013). There are also genetic disorders that are inherited by the person and can vary in how much they affect the person and when they surface (2013).
Though the majority of these health issues are preventable, a major contributor to global ill health is the fact that approximately 1 billion people lack access to health care systems (Shah, 2014). Arguably, the most common and harmful health issue is that a great many people do not have access to quality remedies.
Main article: Mental health
The World Health Organization describes mental health as "a state of well-being in which the individual realizes his or her own abilities, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to his or her community". Mental Health is not just the absence of mental illness.
Mental illness is described as 'the spectrum of cognitive, emotional, and behavioral conditions that interfere with social and emotional well-being and the lives and productivity of people. Having a mental illness can seriously impair, temporarily or permanently, the mental functioning of a person. Other terms include: 'mental health problem', 'illness', 'disorder', 'dysfunction'.
Roughly a quarter of all adults 18 and over in the US are considered diagnosable with mental illness. Mental illnesses are the leading cause of disability in the US and Canada. Examples include, schizophrenia, ADHD, major depressive disorder, bipolar disorder, anxiety disorder, post-traumatic stress disorder and autism.
Many teens suffer from mental health issues in response to the pressures of society and social problems they encounter. Some of the key mental health issues seen in teens are: depression, eating disorders, and drug abuse. There are many ways to prevent these health issues from occurring such as communicating well with a teen suffering from mental health issues. Mental health can be treated and be attentive to teens' behavior.
Many factors contribute to mental health problems, including:
- Biological factors, such as genes or brain chemistry
- Life experiences, such as trauma or abuse
- Family history of mental health problems
Achieving and maintaining health is an ongoing process, shaped by both the evolution of health care knowledge and practices as well as personal strategies and organized interventions for staying healthy.
Main articles: Healthy diet and Human nutrition
An important way to maintain your personal health is to have a healthy diet. A healthy diet includes a variety of plant-based and animal-based foods that provide nutrients to your body. Such nutrients give you energy and keep your body running. Nutrients help build and strengthen bones, muscles, and tendons and also regulate body processes (i.e. blood pressure). The food guide pyramid is a pyramid-shaped guide of healthy foods divided into sections. Each section shows the recommended intake for each food group (i.e. Protein, Fat, Carbohydrates, and Sugars). Making healthy food choices is important because it can lower your risk of heart disease, developing some types of cancer, and it will contribute to maintaining a healthy weight.
The Mediterranean diet is commonly associated with health-promoting effects due to the fact that it contains some bioactive compounds like phenolic compounds, isoprenoids and alkaloids.
Main article: Physical exercise
Physical exercise enhances or maintains physical fitness and overall health and wellness. It strengthens muscles and improves the cardiovascular system. According to the National Institute of Health (NIH) there are four types of exercise; Endurance, Strength, Flexibility, and Balance. Endurance exercises are those that will elevate your heart rate including; walking, jogging, running, hiking etc. 
Main articles: Sleep and Sleep deprivation
Sleep is an essential component to maintaining health. In children, sleep is also vital for growth and development. Ongoing sleep deprivation has been linked to an increased risk for some chronic health problems. In addition, sleep deprivation has been shown to correlate with both increased susceptibility to illness and slower recovery times from illness. In one study, people with chronic insufficient sleep, set as six hours of sleep a night or less, were found to be four times more likely to catch a cold compared to those who reported sleeping for seven hours or more a night. Due to the role of sleep in regulating metabolism, insufficient sleep may also play a role in weight gain or, conversely, in impeding weight loss. Additionally, in 2007, the International Agency for Research on Cancer, which is the cancer research agency for the World Health Organization, declared that "shiftwork that involves circadian disruption is probably carcinogenic to humans," speaking to the dangers of long-term nighttime work due to its intrusion on sleep. In 2015, the National Sleep Foundation released updated recommendations for sleep duration requirements based on age and concluded that "Individuals who habitually sleep outside the normal range may be exhibiting signs or symptoms of serious health problems or, if done volitionally, may be compromising their health and well-being."
|Age and condition||Sleep Needs|
|Newborns (0–3 months)||14 to 17 hours|
|Infants (4–11 months)||12 to 15 hours|
|Toddlers (1–2 years)||11 to 14 hours|
|Preschoolers (3–5 years)||10 to 13 hours|
|School-age children (6–13 years)||9 to 11 hours|
|Teenagers (14–17 years)||8 to 10 hours|
|Adults (18–64 years)||7 to 9 hours|
|Older Adults (65 years and over)||7 to 8 hours|
Role of science
Main articles: Health science and Health care
Health science is the branch of science focused on health. There are two main approaches to health science: the study and research of the body and health-related issues to understand how humans (and animals) function, and the application of that knowledge to improve health and to prevent and cure diseases and other physical and mental impairments. The science builds on many sub-fields, including biology, biochemistry, physics, epidemiology, pharmacology, medical sociology. Applied health sciences endeavor to better understand and improve human health through applications in areas such as health education, biomedical engineering, biotechnology and public health.
Organized interventions to improve health based on the principles and procedures developed through the health sciences are provided by practitioners trained in medicine, nursing, nutrition, pharmacy, social work, psychology, occupational therapy, physical therapy and other health care professions. Clinical practitioners focus mainly on the health of individuals, while public health practitioners consider the overall health of communities and populations. Workplace wellness programs are increasingly adopted by companies for their value in improving the health and well-being of their employees, as are school health services in order to improve the health and well-being of children.
Role of public health
Main article: Public health
See also: Global health
Public health has been described as "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals." It is concerned with threats to the overall health of a community based on population health analysis. The population in question can be as small as a handful of people or as large as all the inhabitants of several continents (for instance, in the case of a pandemic). Public health has many sub-fields, but typically includes the interdisciplinary categories of epidemiology, biostatistics and health services. Environmental health, community health, behavioral health, and occupational health are also important areas of public health.
The focus of public health interventions is to prevent and manage diseases, injuries and other health conditions through surveillance of cases and the promotion of healthy behavior, communities, and (in aspects relevant to human health) environments. Its aim is to prevent health problems from happening or re-occurring by implementing educational programs, developing policies, administering services and conducting research. In many cases, treating a disease or controlling a pathogen can be vital to preventing it in others, such as during an outbreak. Vaccination programs and distribution of condoms to prevent the spread of communicable diseases are examples of common preventive public health measures, as are educational campaigns to promote vaccination and the use of condoms (including overcoming resistance to such).
Public health also takes various actions to limit the health disparities between different areas of the country and, in some cases, the continent or world. One issue is the access of individuals and communities to health care in terms of financial, geographical or socio-cultural constraints to accessing and using services. Applications of the public health system include the areas of maternal and child health, health services administration, emergency response, and prevention and control of infectious and chronic diseases.
The great positive impact of public health programs is widely acknowledged. Due in part to the policies and actions developed through public health, the 20th century registered a decrease in the mortality rates for infants and children and a continual increase in life expectancy in most parts of the world. For example, it is estimated that life expectancy has increased for Americans by thirty years since 1900, and worldwide by six years since 1990.
Main article: Self care
See also: Chronic care management, Social relation, and Stress management
Personal health depends partially on the active, passive, and assisted cues people observe and adopt about their own health. These include personal actions for preventing or minimizing the effects of a disease, usually a chronic condition, through integrative care. They also include personal hygiene practices to prevent infection and illness, such as bathing and washing hands with soap; brushing and flossing teeth; storing, preparing and handling food safely; and many others. The information gleaned from personal observations of daily living – such as about sleep patterns, exercise behavior, nutritional intake and environmental features – may be used to inform personal decisions and actions (e.g., "I feel tired in the morning so I am going to try sleeping on a different pillow"), as well as clinical decisions and treatment plans (e.g., a patient who notices his or her shoes are tighter than usual may be having exacerbation of left-sided heart failure, and may require diuretic medication to reduce fluid overload).
Personal health also depends partially on the social structure of a person's life. The maintenance of strong social relationships, volunteering, and other social activities have been linked to positive mental health and also increased longevity. One American study among seniors over age 70, found that frequent volunteering was associated with reduced risk of dying compared with older persons who did not volunteer, regardless of physical health status. Another study from Singapore reported that volunteering retirees had significantly better cognitive performance scores, fewer depressive symptoms, and better mental well-being and life satisfaction than non-volunteering retirees.
Prolonged psychological stress may negatively impact health, and has been cited as a factor in cognitive impairment with aging, depressive illness, and expression of disease.Stress management is the application of methods to either reduce stress or increase tolerance to stress. Relaxation techniques are physical methods used to relieve stress. Psychological methods include cognitive therapy, meditation, and positive thinking, which work by reducing response to stress. Improving relevant skills, such as problem solving and time management skills, reduces uncertainty and builds confidence, which also reduces the reaction to stress-causing situations where those skills are applicable.
Main article: Occupational safety and health
In addition to safety risks, many jobs also present risks of disease, illness and other long-term health problems. Among the most common occupational diseases are various forms of pneumoconiosis, including silicosis and coal worker's pneumoconiosis (black lung disease). Asthma is another respiratory illness that many workers are vulnerable to. Workers may also be vulnerable to skin diseases, including eczema, dermatitis, urticaria, sunburn, and skin cancer. Other occupational diseases of concern include carpal tunnel syndrome and lead poisoning.
As the number of service sector jobs has risen in developed countries, more and more jobs have become sedentary, presenting a different array of health problems than those associated with manufacturing and the primary sector. Contemporary problems, such as the growing rate of obesity and issues relating to stress and overwork in many countries, have further complicated the interaction between work and health.
Many governments view occupational health as a social challenge and have formed public organizations to ensure the health and safety of workers. Examples of these include the BritishHealth and Safety Executive and in the United States, the National Institute for Occupational Safety and Health, which conducts research on occupational health and safety, and the Occupational Safety and Health Administration, which handles regulation and policy relating to worker safety and health.
- ^World Health Organization.Constitution of the World Health Organization as adopted by the International Health Conference, New York, 19–22 June 1946; signed on 22 July 1946 by the representatives of 61 States (Official Records of the World Health Organization, no. 2, p. 100) and entered into force on 7 April 1948. In Grad, Frank P. (2002). "The Preamble of the Constitution of the World Health Organization". Bulletin of the World Health Organization. 80 (12): 982.
- ^World Health Organization. (2006). Constitution of the World Health Organization – Basic Documents, Forty-fifth edition, Supplement, October 2006.
- ^Jadad AR, O’Grady L: How should health be defined? (2008). "How should health be defined?". BMJ (Clinical research ed.). 337: a2900. doi:10.1136/bmj.a2900. PMID 19073663.
- ^Callahan D. (1973). "The WHO definition of 'health'". The Hastings Center Studies. 1 (3): 77–87. doi:10.2307/3527467. JSTOR 3527467.
- ^Taylor S, Marandi A (2008). "How should health be defined?". BMJ. 337: a290. doi:10.1136/bmj.a290. PMID 18614520.
- ^Bellieni CV, Buonocore G (2009). "Pleasing desires or pleasing wishes? A new approach to pain definition". Ethics Med. 25 (1): 7.
- ^Sport, Disability and an Original Definition of Health. Zenit.org (February 27, 2013).
- ^"A global conversation on defining health: Alex Jadad and Laura O'Grady – The BMJ". blogs.bmj.com. Retrieved 2018-01-20.
- ^Jadad, Alejandro R.; O’Grady, Laura (2008-12-10). "How should health be defined?". BMJ. 337: a2900. doi:10.1136/bmj.a2900. ISSN 0959-8138. PMID 19073663.
- ^Huber, Machteld; Knottnerus, J. André; Green, Lawrence; Horst, Henriëtte van der; Jadad, Alejandro R.; Kromhout, Daan; Leonard, Brian; Lorig, Kate; Loureiro, Maria Isabel (2011-07-26). "How should we define health?". BMJ. 343: d4163. doi:10.1136/bmj.d4163. ISSN 0959-8138. PMID 21791490.
- ^Stokes, J.; Noren, J.; Shindell, S. (1982-01-01). "Definition of terms and concepts applicable to clinical preventive medicine". Journal of Community Health. 8 (1): 33–41. doi:10.1007/bf01324395. ISSN 0094-5145. PMID 6764783.
- ^World Health Organization (1958). The first ten years of the World Health Organization. Geneva: WHO.
- ^ ab"Part 1 – Theory: Thinking About Health Chapter 1 Concepts of Health and Illness". phprimer.afmc.ca. Retrieved 2016-06-22.
- ^World Health Organization. Regional Office for Europe (1984). Health promotion : a discussion document on the concept and principles : summary report of the Working Group on Concept and Principles of Health Promotion, Copenhagen, 9–13 July 1984 (ICP/HSR 602(m01)5 p). Copenhagen: WHO Regional Office for Europe.
- ^Federal Prevention InitiativesArchived 2016-06-15 at the Wayback Machine.. U.S. Department of Health and Human Services
- ^History & Development of Healthy People. U.S. Department of Health and Human Services
- ^Jonathan, E. Fielding; Shiriki, Kumanyika; Ronald, W. Manderscheid (2013). "A Perspective on the Development of the Healthy People 2020 Framework for Improving U.S. Population Health"(PDF). Public Health Reviews. 35. Archived from the original on 2014-04-02.
- ^"BBC News – How stressed are you?". Bbc.co.uk. 2013-11-06. Retrieved 2014-03-01.
- ^Jadad, Alejandro R. (2016-11-01). "Creating a pandemic of health: What is the role of digital technologies?". Journal of Public Health Policy. 37 (2): 260–268. doi:10.1057/s41271-016-0016-1. ISSN 0197-5897.
- ^"Creating a Pandemic of Health: Opportunities and Lessons for a University Initiative at the Intersection of Health, Equity, and Innovation | Harvard Public Health Review: A Student Publication". harvardpublichealthreview.org. Retrieved 2018-01-20.
- ^Simandan, D., 2018. Rethinking the health consequences of social class and social mobility. Social Science & Medicine. https://doi.org/10.1016/j.socscimed.2017.11.037
- ^ abcWorld Health Organization. The determinants of health. Geneva. Accessed 12 May 2011.
- ^Public Health Agency of Canada. What Determines Health? Ottawa. Accessed 12 May 2011.
- ^ abcLalonde, Marc (1974). "A New Perspective on the Health of Canadians." Ottawa: Minister of Supply and Services. Archived 2014-10-28 at the Wayback Machine.
- ^Andreyeva, Tatiana; Chaloupka, Frank J.; Brownell, Kelly D. "Estimating the potential of taxes on sugar-sweetened beverages to reduce consumption and generate revenue". Preventive Medicine. 52 (6): 413–416. doi:10.1016/j.ypmed.2011.03.013.
- ^Housman, Jeff; Dorman, Steve (September–October 2005). "The Alameda County Study: A Systematic, Chronological Review"(PDF). American Journal of Health Education. Reston, VA: American Alliance for Health, Physical Education, Recreation and Dance. 36 (5): 302–308. doi:10.1080/19325037.2005.10608200. ISSN 1055-6699. ERIC document number EJ792845. Retrieved 27 December 2011.
- ^World Health Organization. The world health report. Geneva.
- ^Georgia State University. 1998. Health Triangle Slides.
- ^Nutter S. (2003) The Health Triangle. Anchor Points, Inc., ISBN 0974876003.
- ^World Health Organization. The Ottawa Charter for Health Promotion. Adopted at the First International Conference on Health Promotion, Ottawa, 21 November 1986 – WHO/HPR/HEP/95.1.
- ^Housman & Dorman 2005, pp. 303–304. "The linear model supported previous findings, including regular exercise, limited alcohol consumption, abstinence from smoking, sleeping 7–8 hours a night, and maintenance of a healthy weight play an important role in promoting longevity and delaying illness and death." Citing Wingard DL, Berkman LF, Brand RJ (1982). "A multivariate analysis of health-related practices: a nine-year mortality follow-up of the Alameda County Study". Am J Epidemiol. 116 (5): 765–775. PMID 7148802.
- ^Jadad, A.R. (2013). "On Living a Long, Healthy, and Happy Life, Full of Love, and with no Regrets, until Our Last Breath". Verhaltenstherapie. 23 (4): 287–289. doi:10.1159/000357490.
- ^UNESCO. The UN World Water Development Report: Facts and Figures – Meeting basic needs. Accessed 12 May 2011.
- ^Björk J, Albin M, Grahn P, Jacobsson H, Ardö J, Wadbro J, Ostergren PO (2008). "Recreational Values of the Natural Environment in Relation to Neighborhood Satisfaction, Physical Activity, Obesity and Well being". Journal of Epidemiology & Community Health. 62 (4): e2. doi:10.1136/jech.2007.062414. PMID 18365329.
- ^Advances in Human Factors, Business Management, Training and Education | SpringerLink. doi:10.1007/978-3-319-42070-7.