BEFORE ADVISING THE DIET PLAN AND EXERCISE REGIMEN
It is important to make people with diabetes understand the need for alterations in their dietary habits. An understanding of the eating and cooking habits of the family, the type of food consumed and the normal pattern of meals, helps in planning nutritional therapy. A process involving the person with diabetes and his/her family in discussions regarding the appropriate diet to be consumed helps compliance. If people with diabetes are a part of this process, they would implement modifications more effectively in their daily routine. Decisions must not be forced on the patient. The factors that need to be taken into consideration before giving dietary advice include:

1. Type of diabetes mellitus, presence of co-morbid conditions and/or complications

2. Current drug regimen

3. Treatment goals, e.g. weight loss, target blood glucose levels, blood lipid levels, prevention of hypoglycaemia, etc.

4. Educational and psychosocial background of the person with diabetes

5. Willingness to follow advice and actual capability of the person to adhere to the advice based on his/her physical, psychological, financial conditions and also his/her responsibilities towards work, family, etc.

PLANNING THE DIET
The pharmacokinetics of a person’s medications need to be understood while individualizing the nutrition and exercise plan. People with diabetes should be explained the relationship between their medications and various nutrients and physical activity to prevent them from overdoing any aspect of the dietary and exercise plan. Based on the drug(s) that a person is receiving, alterations need to be made to the dietary plan. Some of these are:

1. Insulin sensitizers (metformin and glitazones): The total amount of macronutrients can be distributed over meals with greater flexibility without fear of hypoglycaemia.

2. Insulin secretagogues (sulphonylureas, glinides) and conventional insulin therapy: They must be prescribed snacks or split meal patterns to match insulin levels in the body as well as to avoid hypoglycaemia in later hours.

3. Bedtime glargine or detemir insulin: While most people do not need a bedtime snack, this should not be ruled out.

4. People on insulin lispro or aspart as their premeal insulin regimen do not need mid-morning and afternoon snacks, but if the bedtime insulin is either NPH or insulin–zinc suspension, they need complex or high fibre carbohydrates in their bedtime snack.

5. People receiving drugs which retard the breakdown and/or absorption of carbohydrates (e.g. alpha glucosidase inhibitors) should be prescribed a lower amount of fibre for the major meal with which the drug is taken and snacks with more fibre should be given.

The main considerations in prescribing macronutrients are explained in Table I.

1. Advise patients to reduce the use of oil and other fatty seasonings gradually so as to avoid aversion from foods cooked in very low quantities of fat.

2. Using less spices to match the small quantity of oil or other fatty seasonings gives an unchanged flavour to the dish and makes it equally palatable.

3. Use alternative methods of cooking such as non-stick utensils, boiling, grilling, etc.

1. Delay the absorption of macronutrients and hence prevent a postprandial blood glucose surge.

2. Help provide a feeling of satiety because of their bulk and prevent overeating.

3. Delay absorption and retard the breakdown of carbohydrates, thus maintaining postprandial blood glucose levels evenly over a period. In this manner fibres help reduce hypoglycaemic episodes.

4. Reduce hyperinsulinaemia and lipaemia.

Micronutrients
Much has been written and discussed about the use of micro-nutrients in people with diabetes. However, no study has proven the need to supplement micronutrients over and above the
daily recommended requirements. Optimum micronutrients can be derived from a diet with an optimal composition of macro-nutrients and minimally processed food items. There may be a need to supplement micronutrients in individual patients, and
this should be carefully evaluated.

Snacks or split meals
In India, traditionally, people are used to larger meals. For many people with diabetes, splitting a large meal into 2 small meals spaced at 3–4-hour intervals is advised. Alternatively, a healthy snack option (fruits, nuts, etc.) after a moderate meal can be introduced. The initial discomfort of ‘not feeling full’ can be overcome by giving options of eating low or non-caloric food items such as vegetable salads, egg white, etc. A major meal and a snack following that meal should have a calorie and carbohydrate distribution in a ratio of 2:1. While some people feel eating frequently is socially unacceptable, it is important to emphasize the benefits of small, frequent meals and ask people to ignore the discomfort which is usually short-lived. The system of split meals or snacks has many benefits.

1. It improves postprandial glycaemic response.

2. It improves insulin sensitivity.

3. It helps match the pharmacokinetics of insulin or other insulin-secreting drugs and hence provides optimum glycaemia.

Food exchange
Food exchange, whereby one food item can be exchanged with another, provides variety and a balance of macronutrients in a fixed diet plan. Some examples are:

1. Instead of 2 whole wheat chapattis (60 g each), 1 chapatti and 120 g of cooked rice (1 full bowl) can be used.

2. A 110 g jawar roti (about 2 medium size, thin), or 1 restaurant nan/thick roti can replace 2 chapattis.

3. 200 g of the edible part of a watermelon (about 5–6 slices) can replace 1 whole orange (about 120 g) or 1 apple or 1 medium size banana or half a custard apple or a 90 g (small) chicku.

4. 4–5 whole almonds and 4 dry dates can replace 1 cup of coffee and 4 biscuits.

5. Half a chapatti or half a bowl of rice can be replaced with a scoop of ice cream.

6. In case an oily restaurant meal is taken, the quantity of oil and ghee in the next meal can be decreased.

7. 2 slices of bread in a sandwich (with a bit of butter and cucumber slices) can be replaced by 2 medium size idlis
   (30 g each) with vegetable sambar.

8. One boiled egg white can replace 50 g of boiled/grilled fish
   (2 small pieces) or a 50 g piece of chicken.

9. 1 bowl of sprouts with some onion and tomato can be exchanged with 1 bowl of curd and some salad.

Calorie requirements
For weight maintenance, about 30 kcal/kg/day are required for a person with moderate physical activity. For weight loss, a person must be given a 30 kcal/kg/day diet plan to start with. Subsequently, a slow reduction in calorie intake up to 20 kcal/kg/day along with moderate physical activity needs to be recommended during follow up visits.

EXERCISE

1. Nutrition therapy and moderate physical activities have been proven to reduce insulin resistance independent of weight loss.

2. Any aerobic exercise, moderate in intensity, lasting for 30–45 minutes per day, done for at least 5 days in a week considerably improves metabolism.

3. Aerobic exercises include brisk walking, cycling, jogging, dancing, swimming, etc.

4. To ensure medical fitness, people should be advised to start slowly and to keep increasing the intensity and duration of exercise gradually over a period of 15 days to 1 month.

5. General safety measures should be emphasized such as using good-fitting footwear, ensuring good vision, carrying an identity card and carbohydrate-rich food items while exercising, etc.

6. If any new symptoms appear, these need to be looked into and investigated, if necessary. These include chest pain, dyspnoea, pain in the lower limbs, blisters on the feet, an increase in hypoglycaemic episodes, etc.

7. Women with knee problems and people with a diabetic foot need to be encouraged to do upper body exercises.

People with type 2 diabetes mellitus
Though weight loss for people with diabetes has been a commonly expected end result of nutrition and exercise therapy, recent studies show that weight maintenance can also help improve insulin sensitivity and yield desirable metabolic goals.3Some possible regimens that could be used for people with type 2 diabetes are shown in Figs 1–3.

People with type 1 diabetes mellitus
Carbohydrate counting is a method of carbohydrate monitoring whereby bolus doses of insulin are matched to the amount of carbohydrates eaten per meal. This method has been proven to be helpful for people with type 1 diabetes to achieve optimum blood glucose control and a good quality of life. 4
   Though initially people with type 1 diabetes do not present with metabolic disasters such as insulin resistance and lipid disturbances, it is wise to introduce a habit of healthy diet patterns to avoid future weight gain and other metabolic derangements (Fig. 4).