With increased incidence and prevalence of lifestyle diseases, concept of healthy and balanced diet has become the most important tool for a good 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).
Various dietary requirements if not met properly has shown its effects in health deterioration and changes in the same has wonderfully improved general health. The World Health Organization (WHO) makes the following 5 recommendations with respect to both populations and individuals:
- Eat roughly the same amount of calories that your body is using. A healthy weight is a balance between energy consumed and energy that is ‘burnt off’
- Limit intake of fats, and prefer unsaturated fats to saturated fats and trans fats
- Increase consumption of plant foods, particularly fruits, vegetables, legumes, whole grains and nuts
- Limit the intake of sugar. We recommends less than 10% of calorie intake from simple sugars
- Limit salt / sodium consumption from all sources and ensure that salt is iodized.
- Other recommendations include
- 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)
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. 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 it 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”. Evidence shows that the Mediterranean diet improves cardiovascular outcomes.
WHO recommends few standards such as an intake of less than 5 grams per person per day so as to prevent one from cardiovascular disease. Unsaturated fatty acids with polyunsaturated vegetable oils, on the other hand plays an essential role in reducing coronary heart disease risk as well as diabetes.
Weight control diets aim to maintain a controlled weight. In most cases dieting is used in combination with physical exercise to lose weight in those who are overweight or obese.
Diets to promote weight loss are divided into four categories: low-fat, low-carbohydrate, low-calorie, and very low calorie.
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.
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.
Thus, it can be easily concluded that diet plays a very important role in maintaining health and preventing diseases and utmost importance should be given to healthy eating habits.