A healthy diet is one that helps to maintain or improve overall health.
A healthy diet provides the body with essential nutrition: fluid, adequate essential amino acids from protein, essential fatty acids, vitamins, minerals, and adequate calories. The requirements for a healthy diet can be met from a variety of plant-based and animal-based foods. A healthy diet supports energy needs and provides for human nutrition without exposure to toxicity or excessive weight gain from consuming excessive amounts. Where lack of calories is not an issue, a properly balanced diet (in addition to exercise) is also 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 the public 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).
Healthy eating is simple, according to Marion Nestle, who expresses the mainstream view among scientists who study nutrition:
| Food group/subgroup (units) |
Healthy US patterns |
Healthy Vegetarian patterns |
Healthy Med-style patterns |
| Fruits (cup eq) |
2 |
2 |
2.5 |
| Vegetables (cup eq) |
2.5 |
2.5 |
2.5 |
| Dark green |
1.5/wk |
1.5/wk |
1.5/wk |
| Red/orange |
5.5/wk |
5.5/wk |
5.5/wk |
| Starchy |
5/wk |
5/wk |
5/wk |
| Legumes |
1.5/wk |
3/wk |
1.5/wk |
| Others |
4/wk |
4/wk |
4/wk |
| Grains (oz eq) |
6 |
6.5 |
6 |
| Whole |
3 |
3.5 |
3 |
| Refined |
3 |
3 |
3 |
| 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 |
| Poultry |
10.5/wk |
-- |
10.5/wk |
| Seafood |
8/wk |
-- |
15/wk |
| Eggs |
3/wk |
3/wk |
3/wk |
| Nuts/seeds |
4/wk |
7/wk |
4/wk |
| Processed Soy (including tofu) |
0.5/wk |
8/wk |
0.5/wk |
| Oils (grams) |
27 |
27 |
27 |
| Solid fats limit (grams) |
18 |
21 |
17 |
| Added sugars limit (grams) |
30 |
36 |
29 |
- Essential micronutrients such as 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).
- 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.
-
Calcium is important, but milk is not its best or only source. Good sources of calcium are collards, bok choy, fortified soy milk, baked beans, and supplements which contain calcium and vitamin D.
-
Water is the best source of liquid. 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.
- Moderate alcohol drinking has health benefits, but is not recommended for everyone.
- Daily multivitamin and extra vitamin D intake has potential health benefits.
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Wikipedia
