Do you know that the first vitamins were isolated and chemically defined only in the 1930s when Vitamin C was documented and thiamine was isolated and synthesised as Vitamin B1 After these discoveries, began the importance of framing dietary guidelines to preventnutritional deficiencies. In 1941, thefirst RDAs were announced which laid the foundation for providing guidelines for total calories and selected nutrients including protein, calcium, phosphorus, iron, and specific vitamins.These historical events eventually led to food fortification of selected staple foods as nutrition research began to link single nutrients with specific diseases.
Diets are composed of foods, which in turn are composed of nutrients and other food components.Dietary guidelines are therefore important since they provide evidence about the food choices consumers can make to meet their nutritional requirements so that these foods can
- deliver optimal nutrients to meet their daily needs
- reduce the risk of prevailing chronic and non-communicable disease
Dietary guidelines also provide benchmarks for evaluating overall diet including upper limits of saturated fat added sugar and salt and help consumers to decide on what foods are essential for their health. If there is inadequate consumption of vitamins it can cause deficiencies and over-consumption can lead to obesity.
Economic development, modernisation of agriculture and food processing as well as new food formulation techniques and fortification have led to reducing single nutrient deficiency diseases. However, they have also brought forth diet related diseases like obesity, type 2 diabetes, and some types of cancers. Therefore, dietary guidelines are important as they lay down the principles for processed foods so these foods do not lead to lifestyle diseases. They lay down guidelines so the processed foods can be formulated with low fat, salt and sugar and yet fortified with the right amounts of micronutrients and fibre.
This is especially important for India where a dietary transition from traditional diets to more ‘westernised’ way of eating is being adopted and not all for the good. Indians have begun to consume excess of calories, saturated fats, trans fatty acids, simple sugars, salt and there is low intake of fibre. This change in diets coupled with sedentary lifestyle is leading to an increase in obesity and diet-related non-communicable diseases such as type II diabetes and cardiovascular disease especially in urban areas but also to some extent in semi-urban and rural areas. A large number of productive years are lost due to unhealthy diets leading to non-communicable diseases. Accordingly, dietary guidelines now recommend
- reduced intake of carbohydrates
- preferential intake of complex carbohydrates
- low glycaemic index foods
- higher intake of fibre
- lower intake of saturated fats
- optimal ratio of essential fatty acids
- reduction in trans fatty acids
- slightly higher protein intake
- lower intake of salt
- restricted intake of sugar
These dietary guidelines will help curb the increase in cases of obesity, hypertension metabolic syndrome, hypertension, Type II diabetes and cardio-vascular diseases.
Another area of poor dietary patterns of Indians,which has been highlighted by various research studies is that Indians have micronutrient deficiencies because of the poor intake of fruits and vegetables. Fruits and vegetables, being rich sources of antioxidants, fibre and other micronutrients should make a generous portion of an individual’s diet. However, majority of the people consume far lesser than the daily recommended level of fruits and vegetables and milk in India.In fact, low fruit and vegetable intake is the sixth on WHO’s list of 20 risk factors for mortality worldwide.
The WHO and also ICMR-NIN recommend a daily intake of at least 400 grams of fruits and vegetables (excluding potatoes and other starchy tubers) to prevent diet-related chronic diseases and micronutrient deficiencies. Micronutrients are an important part of diets as they prevent anaemia and stunting and diets that lack micronutrients increase risk of inflammation and insulin resistance. Lack of fruits and vegetables in the diet can also affect learning ability and memory. The phytochemicals found in fruits and vegetables are metabolized to polyphenols and phenolic acids, which are anti-inflammatory, antioxidative, anti-ageing and cancer preventive.
Studies in Indian diets have found that there is a relationship between dietary patterns and body size, hypertension, diabetes and cholesterol levels. There is also evidence of health risks where a major portion of the diets consists of snacks and these are usually high-fat, high-salt fried foods that may also be high in trans-fats. A dietary pattern high in sweets and snacks has been associated with greater risk of diabetes compared with a traditional diet high in rice and pulses.On the other hand, a varied diet high in fruits, vegetables, pulses and nuts has been associated with lower cholesterol, indicating that more traditional diets may have a healthier profile.
In India most dietary patterns are vegetarian and there is a variability from region to region.In some places, diets are characterised by consumption of wheat, fruit and sweets and not by vegetables. Dietary patterns from the East and South were also more likely to be defined by meat or fish consumption than those from the North and West which are characterised by rice, fruits vegetables and pulses. As per recommendation of the National Institute of Nutrition (Indian Council of Medical Research), Hyderabad, India, an individual is advised to consume food from at least 9 to 10 food groups per day to achieve diet with adequate micronutrients and quality protein and fat. Dietary diversity ensures adequacy of essential amino acids, fatty acids and micronutrient for optimal physical and mental health. Dietary intakes of children and adults in rural and urban areas show gross inadequacy of all nutrients and poor quality of protein.
“My Healthy Plate for the Day” to prevent hidden hunger and protection from disease (given below in image) has been designed by the ICMR-National Institute of Nutrition, and recommends sourcing of macronutrients and micronutrients from minimum of 8 food groups per day to achieve a balanced diet that would fulfil the required calorie or energy needs of Indians. It can easily be seen that fruits and vegetables make up half of the required sources in a balanced diet.