Healthy diet

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A healthy diet contains a balance of food groups and all the nutrients necessary to promote good health. Human nutrition is enormously complex and a healthy diet may vary widely according to an individual's genetic makeup, environment, and health.

Healthy eating is the practice of making choices about what and/or how much one eats with the intention of improving or maintaining good health. Typically, this means following recommendations for a healthy diet.

The concept of healthy eating is primarily a problem in rich countries where the lifestyle includes a modicum of outdoor physical activities, high but not always high-quality food consumption, and a trend towards industrially-produced foods instead of locally-sourced, locally-prepared meals. The article below discusses the recommendations for most citizens of such countries, written from an admittedly developed world point of view. Unfortunately, the main food problems for most of the people in the planet are lack thereof or malnutrition.

Generally, a healthy diet will include:

1. Sufficient calories to maintain a person's metabolic and activity needs, but not so excessive as to result in fat storage greater than roughly 12% of body mass^[1];
2. Sufficient fat, consisting mostly of mono- and polyunsaturated fats (avoiding saturated and "trans" fats) and with a balance of omega-6 and long-chain omega-3 lipids;
3. Sufficient essential amino acids ("complete protein") to provide cellular replenishment and transport proteins;
4. Essential micronutrients such as vitamins and certain minerals.
5. Avoiding directly poisonous (e.g. heavy metals) and carcinogenic (e.g. benzene) substances;
6. Avoiding foods contaminated by human pathogens (e.g. e. coli, tapeworm eggs).
7. Avoiding chronic high doses of certain foods that are benign or beneficial in small or occasional doses, such as

• foods or substances with directly toxic properties if chronically ingested at high doses (e.g. chickpeas, ethyl alcohol, Vitamin A);
• foods that may interfere at high doses with other body processes (e.g. table salt);
• foods that may burden or exhaust normal functions (especially refined carbohydrates eaten without adequate dietary fiber).

In specific individuals, ingesting foods containing natural allergens (e.g. peanuts, shellfood) or drug-induced allergens (e.g. tyramine for a person taking an MAO inhibitor) may be life-threatening.

Contents 1 Healthy diet 1.1 Definition 1.2 Food 1.3 How much to eat? 1.4 Regulation of intake 1.5 Eating more or less of particular nutrients 2 Government involvement 2.1 Nutritional advice 2.2 Problems with government approaches 3 Benefits of eating routines for young children 4 Toxins 4.1 Food additives 5 See also 6 Footnotes 7 References 8 External links

[edit] Healthy diet

A reliance on a single food which composes the majority of a diet (such as Big Macs) is a poor eating habit. An individual on such a diet may be prone to deficiency, and most certainly will not be fulfilling the Recommended Nutrient Intake of every nutrient.

While plants, vegetables and fruits are known to help reduce the incidence of chronic disease, ^[1], the benefits on health posed by plant-based foods, as well as the percentage of which a diet needs to be plant based in order to have health benefits is unknown. Nevertheless, plant-based food diets in society and between nutritionist circles are linked to health and longevity, as well as contributing to lowering cholesterol, weight loss, and in some cases, stress reduction. ^[2]

Although a number of preconceptions of a healthy diet center around plant based foods, the majority of assumptions about foods which are usually thought of as "bad" foods are usually correct. Apart from the assumption that there are "bad" foods, many people associate dishes such as Full English cooked Breakfast and Bacon Sandwiches as foods which, if eaten regularly, can contribute to cholesterol, fat and heart problems.

[edit] Definition

A healthy and balanced diet is usually defined as a diet in which nutrient intake is maintained, and cholesterol, salt, sugar and fat are reduced. The idea of a healthy diet is often used by a government to ensure that people are well "protected" against common illnesses, as well as conditions which stem from poor diet; of which everything from headaches, lessened sexual drive, to heart disease, alcohol poisoning, and obesity may be attributed.^[3]

The definition of a healthy diet by some is also thought of as a diet which will combat or prevent illness. When eating healthy, the likelihood of succumbing to common minor illnesses, such as lesser forms of Influenza, is decreased, mainly because consumption of a healthy diet would provide ample nutrients and energy for the body, so as to help stave off such illnesses. Similarly, a healthy diet will aid the body during recovery from illness.If you do not have Fruits and Vegetables in your diet their is a 98% chance you will die or become terribly ill by the age of 8. The myth of "Starve a cold, feed a fever" is a common misconception, particularly in the United Kingdom. This is a myth in every sense of the word because providing the body with nutrients during illness is actually beneficial - nutrient and energy stores would be replenished, allowing for more energy to be used by the body to combat illness. Interestingly, it is a myth that has arisen through people who do not understand the advice that they are repeating. It should be noted that a cold and fever are not opposites, but instead a fever is a possible symptom of a cold; and so the original meaning is the opposite of that which is intended. Essentially the meaning is a cause and effect. Written out clearly and fully, the true meaning would be "If you starve a cold you will feed a fever".

A recent study claims that short term "starve a fever, feed a cold" might actually be correct depending on the underlying cause of the fever. Eating and fasting causes brief fluctuations in the amount of two chemical messengers called cytokines.

After a meal, the average level of cytokine gamma interferon (INF-gamma) in the blood of six volunteers increased by 450%. INF-gamma stimulates the body's defense against chronic infections associated with colds. INF-gamma triggers the release of white cells that destroy infected cells.

Volunteers who did not eat a meal had low INF-gamma levels but far higher concentrations of another cytokine called interleukin-4 (IL-4). ILa-4 is associated with the production of antibodies, the protein molecules that form the front line defense against acute infections , the kind that most often produce fevers. It would be interesting to see what a more comprehensive sampling of individuals might reveal.;.

The importance at present of a healthy diet is something which is actually receiving many promotions throughout several countries due to obesity epidemics. Governments, particularly in the United Kingdom, through the advice of the Department of Health, introduced a public health white paper to parliament, CM 6374, which aimed to deal with the issues presented by particularly imported culture - cigarettes, alcohol and fast food all being produced in their majority in the United States, or by US-based companies. ^[4]

[edit] Food

There are no foods which are intrinsically linked on a singular-consumption basis to illness, disease or decline of body function. Yet, there are foods, such as fugu, which when improperly cut or prepared can result in death. In essence, "there are no bad foods"^[5].

Nevertheless, there are foods which have low nutritional value, and if consumed on a regular basis will contribute to the decline of human health. This has been demonstrated in the documentary film, Supersize Me, as well as by various epidemilogical studies which have determined that foods such as processed and fast foods, are linked to diabetes and various heart problems. ^{[6] [7]}

The popular perception of achieving a healthy diet through the eating of "healthy" foods may be misunderstood. Indeed, ideas of what counts as "healthy" have varied in different times and places, according to scientific advances in the field of nutrition, cultural fashions, religious proscriptions, or personal considerations. The consumption of nothing but substances which are deemed healthy, such as an "all-grain diet" or a diet consisting only of pasta or other health-foods, would most likely result in nutritional deficiencies because important staples of the meal were missing, like protein-based foods. Foods such as grains, fish, corn, etc. are healthy when consumed with a balanced diet, because they supply us with the correct balance of required nutrients. With any diet, the most important aspect is maintaining a healthy intake and balance of foods.

Foods which are considered to be rich in one or more nutrients are seen to be healthy because they are nutrient rich, and if eaten sensibly, will easily regenerate nutrients used naturally throughout the day. But, eating one or more foods which are considered healthy does not mean that a diet that was lacking will immediately be made healthy. The balance of micronutrients gained from both meat, vegetables, and other foods is the feature which makes diets healthy, not only "healthy" foods. ^[8]

From a psychological perspective, a new healthy diet may be difficult to achieve for a person used to eating "bad foods". This may be due to habits acquired in early adolescence and preferences for fatty foods. It may be easier for such a person to transition to a healthy diet if treats such as chocolate are allowed; sweets may act as mood stabilisers, which could help achieve reinforce correct nutrient intake. ^[9]

Some foods within a diet provide a source of many nutrients in varying amounts, while others provide nutrients in large amounts as a singularity; still others have very low nutrient ratings, such as fried, deep-fried and fast foods which are high in calories, but low in nutrients^[10]; e.g a "USA" Big-Mac contains 560 calories, and has over 17% fat, way above the remit of 15% containing sugar, salt and fat. ^[11]

[edit] How much to eat?

As BMI and weight changes from person to person, the general RNI set by governmental institutions may be somewhat lacking for some people, despite the fact that the RNI is generally calculated as higher than the average nutrient intake. It is even thought that some people may have needs above that of the RNI, meaning even if a person achieved nutrient intake, they would still not be fulfilling the RNI. The only real way to know the RNI for a person is to implicitly monitor the intake of nutrients and amount of exercise.^[12]

It is known that the experiences we have in childhood relating to consumption of food affect our perspective on food consumption in later life. From this, we are able to determine ourselves our limits of how much we will eat, as well as foods we will not eat - which can develop into eating disorders, such as anorexia or bulimia nervosa. This is also true with how we perceive the sizes of the meals or amounts of food we consume daily; people have different interpretations of small and large meals based on upbringing, but "replica foods" (which represent the average serving size) can establish the difference in portion size for the individual. ^[13]

[edit] Regulation of intake

The regulation of food and nutrients means decreasing or increasing the amount of nutrients or calories within the diet. Most of the responses to foods within a diet come from people's innate belief that there are 'good' and 'bad' foods. It is from that belief that people most often develop bad diets, because they believe that eating foods which they consider healthy in abundance will create a healthy diet. However, this could not be further from the truth.

From this response, an individual must learn that there are no bad foods, and learn to follow the guidelines their state sets for a healthy diet. These usually range slightly from country to country based on demographics, but usually the same guidelines of eating less fried or fatty foods to reduce cholesterol, and even replacing certain foods with healthier alternative, "healthy" indicating foods which contain both the same or more energy as the original food, but have an abundance of nutrients, for instance: foods such as legumes or beans, within a salad or pasta.

The ingredient usually cited as being most crucial to good health, water, has even been known to result in death when consumed in extraordinary quantities. Deaths from excessive water drinking have generally occurred in persons who are or who have recently been under the influence of hard drugs; for example, MDMA (ecstasy); and in non-elite athletes, according to a 2005 paper in the New England Journal of Medicine over-hydration resulting in "Hyponatremia has emerged as an important cause of race-related death and life-threatening illness among marathon runners".^[2]

[edit] Eating more or less of particular nutrients

In terms of nutrients, it is known from several surveys from the MAFF, and from various studies by the NHS, that the foods which people usually eat on average tend to be closer towards fast food, or ready meals, most of which do not provide a balanced meal, and contribute to major nutrient deficiencies.

From this, people should be able, from governmental guidelines, to decide what amounts of nutrients they have in their diets and increase or decline intakes accordingly. However, people don't eat foods and not nutrients, and few people know which foods stock which nutrients, so allowing people to self-regulate their diets means that they run the obvious risk of deficiency. ^[14]

However, even with pamphlets and other media, the values of which nutrients come from which foods, and the effect of foods on a diet is a difficult decision. For instance, milk, cheese, and other dairy products are known to have a relatively high fat content, and it would be thought that those things with high fat content should be removed from a healthy diet. However, when looking at the food, the more important factor is whether the food has an overall good effect on the diet. For instance, removing such dairy products from a healthy diet may lower fat intake, but will also have implication on the intakes of calcium and riboflavin that such foods possess.

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. Low density lipoprotein is often prevalent in animal products, such as bacon and egg yolks, whereas high density lipoprotein is more common in plant and fish tissues, such as olive oil and salmon.

Due to the difficulties of educating people about nutrient intake in the past, governments have opted to move towards instructions for what foods to eat rather than what nutrients to ingest. ^[15]

[edit] Government involvement

Throughout the past 50 years, governments throughout the world have been involved in the pursuit of engaging with their constituencies in attempts to help them eat healthily, and to remove strain on the governmental health services. Several problems, however have overshadowed government schemes and involvements; particularly media coverage of mass-produced, processed, "snack" or "sweet" products directly marketed at children.

A recent health campaign by the American government has attempted to impress the purported need to eat copious quantities of fruits and vegetables using the slogan "5 a day". Adverts have given examples of what a portion of fruit or vegetables amounts to, and how 5 or more portions can be incorporated into one's diet.

[edit] Nutritional advice

Many governments and other organizations provide nutritional advice and launch schemes in order to promote healthy eating. Diets which lead to obesity, diabetes, and other medical conditions, are a severe drain of resources for national health providers, and on businesses due to reduced productivity of staff. Moreover, a person's feelings of well-being, self-worth, and overall happiness can be severely diminished by poor dietary habits.^{[citation needed]}

[edit] Problems with government approaches

Particularly within the last five years, there have been attempts by government agencies or institutions to combat the type and amount, and method of media coverage that "Junk" foods have received. Governments also put pressure on businesses to promote healthy food options, and regularly consider measures such as limiting the availability of junk food in state-run schools, and taxing foods which are high in fat. Most recently, the United Kingdom actually removed the rights for McDonalds to advertise its products, as the majority of the foods which were seen to have low nutrient values were aimed at children under the guise of the "Happy Meal".

The main problem with such advertisements for foods is that alcohol and fast food are portrayed as offering excitement, escape and instant gratification. But also that another portion of the problem is also seen to come from the approach that the government has towards a healthy diet; a recent white paper describing that the portrayal of healthy lifestyles by government can seem preachy, boring and too much like hard work. ^[16] This too is also said about the way in which the gap between the government and children, or the average consumer is too large, in that information on health and healthy practices seems to be coming from an amalgamation of sources; television advertisements, within magazines, television programmes and even general talk - this making the ideal of a healthy diet difficult to express to the average consumer. ^[17][18]

The British Heart Foundation released its own, government-funded advertisements, labelled "Food4Thought" which were targeted at children and adults displaying the gory nature of what fast food is generally constitued of - displaying a "censored" sticker over the actual contents of an average processed burger, hot-dog or slice of pizza. ^[19]

[edit] Benefits of eating routines for young children

Children thrive on routines and love to know what and when something is expected of them. Even though every child and family is different, it is important to recognize the benefits consistent routines provide for children. Daily routines help children learn a sense of independence, stability and value.

Eating

Set times for breakfast, lunch and dinner, along with healthy snacks throughout the day to make meal times more relaxed. Most children are happier on a schedule and will become hungry at regular times.

Tips for helping make mealtime a positive experience for children:

• Allow your child to eat at his/her own pace.
• Mealtimes are opportunities for children to learn independence by making choices about food.
• Encourage your child to taste everything, but do not force him/her to eat. Because children are picky eaters by nature, it may be necessary to present them with a new food several times before they actually eat it on their own.
• Serve a variety of healthy foods (perhaps different foods on different days) so your child can get all the essential nutrients even if he/she doesn't eat some of the foods.
• If you don't have junk food in the house or don't put it on the table, your child will get hungry and eat the healthy food.
• According to JR Harris in her book "The Nurture Assumption", the best way to encourage a child to eat a food is to serve it when other children who like it are present so your child can see the other children enjoying it; seeing an adult enjoy the food has little impact.

Additional Resources: [Department of Health and Human Services: Centers for Disease Control and Prevention. Nutrition for everyone: Quick tips: Healthy children, healthy choices.; http://www.cdc.gov/nccdphp/dnpa/nutrition/nutrition_for_everyone/quick_tips/healthy_children.htm]

[The Whole Child: For early care providers. It’s the little things: Daily Routines.; http://www.pbs.org/wholechild/providers/little.html]

[edit] Toxins

Virtually all food contains an appreciable level of toxicity, which does not pose a substantial threat to a robust individual, either because of low concentration, or because the individual can readily eliminate it. See excretion. At increasingly high toxin concentrations, otherwise-edible material can no longer be called "food". See poison, contamination.

[edit] Food additives

Some people claim that food additives, such as artificial sweeteners, colorants, preserving agents, and flavourants may cause health problems even though they were extensively tested before being allowed into the market. For example, artificial colorants are claimed to cause hyperactivity in susceptible children. As another example, people on calorie restricted diets often choose to buy products advertised as "reduced calorie" or "no sugar added". These products contain artificial sweeteners. These are safe to consume in small quantities, and are of low toxicity. Safety studies may well show some advantage in substitutions, product by product. Over a period of time, many different products are approved for sale, each one relying on a study done in isolation, and each one suggesting the artificially sweetened product has fewer associated health problems than equivalent all-natural products. When dieters buy reduced-calorie soft drinks, biscuits, cakes, flavoured water, yogurt, and so on, all may contain combinations of the leading artificial sweeteners aspartame, acesulfame potassium or sucralose. Cumulative doses are at higher levels than those on which the safety studies were based.

The issue of sweetening is just one example. Other taste-enhancing additives (e.g. salt substitutes) or flavourants are also hidden in processed foods and drink, as are colourants. Mandatory food labelling is one attempt to overcome the problem. This invites the consumer to check the ingredients of their foods before consumption. However, the average person has no training in organic chemistry and its nutritional effects. Neither is it practical for individuals to manage score cards recording all the nutrients they consume.

Some would assert that research into the toxicity of many varied artificial ingredients has been inconclusive. The USA's Food and Drug Administration has very stringent requirements for the introduction of new food ingredients, and this includes rigorous testing on animals, where the animals are given exorbitant amounts of these chemicals - far more than humans ever would be likely to consume.

Studies often attempt to determine whether an artificially-produced food additive is potentially carcinogenic, conduicive to heart disease, or possessing of other malicious properties.

A good rule of thumb to remember when reading the results of these studies is that the more widespead a food additive is in existing packaged food, the more likely the studies will conclude said additive to be benign.

[edit] See also

• Nutrition
• Food groups
• Food guide pyramid
• Canada's Food Guide to Healthy Eating
• 5 A Day

• Essential nutrient
• Dietary supplements
  • Amino acids
  • Minerals
  • Nootropics
  • Nutraceuticals
  • Vitamins

• Obesity
  • Childhood obesity
• Junk Food
• Fast Food
• Dieting

• Diets (list)
• Eating
• Food
  • Food (portal)
  • Functional food

• Health
  • Health (portal)
  • Healthy eating pyramid
• Exercise
• Physical fitness
• Life extension
  • Life extension (topic list)

• Orthorexia nervosa (an obsession with healthy eating)

[edit] Footnotes

1. ^ As a practical matter, sufficient caloric intake usually requires significant carbohydrate intake; however, whether this is a necessity for a healthy diet is the topic of a lively ongoing controversy
2. ^ . "Hyponatremia among Runners in the Boston Marathon" (subscription required). Retrieved on 2006-10-04.

[edit] References

1. ↑  MAFF (Ministry of Agriculture, Fisheries and Food) 1990: Eight Guidelines for a healthy diet London: Food Sense
2. ↑  Barasi, Mary E. (2003) Human Nutrition: A Health Perspective London:Arnold
3. ↑  Macdonalds Corporation Quality & Nutrition information - McDonalds USA Big-Mac Nutrition factsheet Mcdonalds Corporation (http://app.mcdonalds.com/bagamcmeal?process=item&itemID=5)
4. ↑  Spurlock, M. Supersize Me - A film of epic Proportions Columbia Tristar
5. ↑  Nestle, M. (1998) Animal v plant foods in human diets and health - Proceedings of the Nutrition Society
6. ↑  National Health Service (2005) Five a day - a guide to healthy eating NHS Press (http://www.5aday.nhs.uk/)
7. ↑  Johnson, R. K. (2000). The 2000 Dietary Guidelines for Americans: foundation of US nutrition policy. - British Nutrition Foundation Nutrition Bulletin 25. p241-248
8. ↑  Achterberg, C., McDonnell, E., Bagby, R. (1994) How to put the Food Guide Pyramid into practice - Jornal of the American Dietetic Association Volume 94 p 1030-1035
9. ↑  United Kingdom Department of Health (2005): Choosing Health: making healthier choices easier -- Public Health White Paper CM 6374 retrieved from: United Kingdom Department of Health Website
10. ↑ United States Department of Agriculture (2005) . MyPyramid - Guidelines for healthy eating - Dietary guidelines for Americans USDA Press/Printing retrieved from United States Department of agriculture - MyPyramid replaces food pyramid guide
11. ↑  Oliver, J., Channel Four (2005) Jamie's School Dinners - Documentary produced for channel four Television Programme.
12. ↑  Food standards Authority (2005) 8 easy steps to keeping a healthy and balanced diet - Eat well, be well retrieved from Eat well, be well website.
13. ↑  National Cancer Institute (2005) Eat five to Nine servings of fruits and vegetables per day retrieved from 5-a-day National Cancer institute
14. ↑  British Heart Foundation (2005). Food4Thought - Campaign against junk food within children's diets. retrieved from British Heart Foundation Food4Thought

[edit] External links

• Diet, Nutrition and the prevention of chronic diseases, by a Joint WHO/FAO Expert consultation (2003)
• Diet & Health — A summary for non specialists by GreenFacts of the above WHO/FAO report.
• [20], info about the UK healty eating initiative.