5 Diabetes friendly diets

The phrase - 'You Are What You Eat!' applies not only to how you look but also to your risk of non-communicable diseases like Diabetes. Diet is one of the pillars for prevention, management and even remission of Type 2 Diabetes.

Diet influences body weight of a person. Excess body weight (over-nutrition) is a predisposing  factor for Diabetes. On the other hand, under-nutrition  (especially in the mother) is now considered  to be a strong risk factor for Diabetes in the subsequent generations. The link between  poor  diet and Diabetes is strengthening.  Diet influences a person's  feelings and vice versa. This means

that stress and diet are closely associated and both affect blood sugar levels.What you eat affects blood sugar level in'•several ways. An incorrect diet can increasethe risk of Diabetes while a correct diet has the potential to prevent or manage Diabetes. To understand the difference between the two requires some basics to be revised. 

Quality

A diverse diet with all its macro and micronutrients is considered to be a healthy diet. Greater the variety of food choices, better is the nutritional profile. When it·  comes to Diabetes, yet another important factor called glycaemic index of foods needs attention. The foods with lower glycaemic index are considered to be 'superior' in quality as they help control blood sugar levels better. Right cooking techniques will further help retain/ deteriorate the glycaernic quality of food. 

Quantity

Considering the quality of the diet is not enough for good control of blood  sugar levels. If an individual eats too much quantity of good quality food, their sugars are likely to increase. Optimal proportion of different  foods needs to be consumed  so that there won't  be too much  of glycaemic load. This can be achieved by portion control at meals (small frequent meals) or by time restricted  eating (intermittent fasting).

Paying attention to both - quality (glycaemic index) and quantity (glycaemic load) is crucial. Diets high in glycaemic index and high in glycaemic load are known to increase the risk of Diabetes by many folds.

Basic principles

All Diabetes friendly diets aim to achieve harmony between  glycaemic index and glycaemic load. Principles of a Diabetes friendly diet are:

•  Diabetes friendly diets consists of all key food groups.

•  They include foods low in glycaemic index.

•  They advise specific quantity of food at meals or advocate time restrictions for meals.

• The diets take into account quality and quantity of fats as well as salt.

• These diets discuss food processing and optimal cooking methods.

As one size does not fit all, one type of Diabetes friendly diet may not be

appropriate for all. The Diabetes friendly diet must be chosen and modified based on following factors:

•  Age of the person and whether they have Type 1 or 2 Diabetes

•  Current treatment (medicines/insulin)

•  Other co-morbidities or presence of Diabetes complications

•   Dietary preferences (vegetarian/ non-vegetarian), cultural factors

•   Work and activity patterns (sedentary/ active)

•   Allergy/intolerances

There are several healthful diets or eating patterns one can follow to manage Diabetes. Let's discuss some of them.

Low carb diet

Carbohydrates in the diet are directly converted to simple sugars. The balance of carbohydrates in the meal needs to be adjusted carefully for a person with Diabetes. Reducing carbohydrate intake is not only effective in controlling blood sugars, but also in reducing body weight. Especially in India, where the traditional diets are dense in carbohydrates, reducing carbohydrates is a practical strategy to get blood sugar levels under control.

Rather than reducing carbohydrates drastically, cutting down on them gradually always works better. For example If a person's diet recall is suggestive of

70 per cent carbohydrate intake, reducing carbs to 60 per cent, then to 50 per cent to 40 per cent is acceptable and sustainable. While designing a low carb diet, it is important to evaluate not only the quantity of carbohydrates but also the quality (type).

A study conducted in Canada and published in the Journal of Nutrition has found that replacing 50 per cent of carbohydrates with lentils (such as beans, peas and split lentils or dal) can lower post meal blood sugar level spikes. The study was conducted on 48 participants without Diabetes or any other health conditions.

Their BMI levels (body mass index) were 20-30 Kg/m2•  The participants were asked to fast for 10-12 hours before the study.

The participants were divided into two - rice and potato groups. The participants of the rice group were randomly provided with 50 g of rice alone and rice with lentils meals. The participants in the potato group were also provided with 50 g potato alone and potatoes with lentils meal. The post meal blood sugar levels of the participants were measured in eight regular intervals of 15 minutes.

The results of the study have shown that the post meal blood sugar levels raise within 15 to 60 minutes of eating rice alone or potatoes alone meals. The blood sugar levels did not rise in the participants who had included lentils rich with rice or potatoes in their meals. Lentils are rich in protein and are digested slow than products

containing starch, such as rice. They cause slower release of sugar in the blood and thus do not raise the post meal blood sugar levels significantly.

A low-carb diet is recommended in people with Type 1 Diabetes as well because it lowers blood sugar levels and reduces insulin requirement. Low carbohydrate diets were an accepted method for treatment of Diabetes prior to the discovery of insulin.

ADA defines low carbohydrate diet as less than 130 g/day or 26 per cent total energy intake from carbohydrates. However, the National Health and Medical Research Council recommends carbohydrates to the level of 45-65 per cent of total energy intake in people with Type 1 Diabetes.

Sustainability and complications

Sustained adherence to a low carb diet appears to be difficult. There is lack of data supporting long-term  efficacy, safety and health benefits of Low Carb High Fat (LCHF) diets. Low carb diets can result in nutritional deficiencies,  namely those commonly  found  in  unprocessed carbohydrate  foods including vitamins, minerals,  dietary fibre and antioxidants.

Ketogenic Diet

Though originally used for treating epilepsy, ketogenic diet is now widely used for blood sugar control and weight loss. As the amount of carbohydrates in this diet is minimal (-20 grams per day), the post meal blood sugar excursions get resolved easily.

Keto diet may help slow progression of Type 2 Diabetes and may even reverse Diabetes by restricting the carbohydrates and reducing the insulin resistance. It has also been found to reduce HbAlc significantly. Keto diet improves insulin

resistance promptly because of ketones per se and low carb intake. This can further result in weight loss. The duration and degree of reduction in insulin resistance depend on various factors like duration of Diabetes, weight, physical activity and the maintenance of ketosis.

Sustainability and complications

The short-term complications of keto diet may occur in the initial keto-adaptation phase which is being referred to as Keto-flu. The symptoms include fatigue, lightheadedness, headache, lethargy,

nausea and constipation. All these symptoms are mild and can be prevented or minimised by increasing salt intake

(1-2 g/day). Constipation can be prevented by increasing the fluid intake.

Hypoglycemia (very low blood sugar levels) and dyslipidemia (imbalance in lipid levels) can also occur. This is an indicator to switch to a less Keto diet with lower fat: carbohydrate ratio. The long-term complications of Keto diet may be growth retardation in children, kidney stones and increase in uric acid.

One needs to have constant vigilance on blood sugar as well as ketone levels to make sure that this diet does not cause any harmful effects.

Ketogenic diet may not be appropriate for all candidates. Before starting with ketogenic diet, it is good to consult a doctor and a nutritionist. Keto diet timelines can only be decided after they review the individual's ability, willingness, health status and the underlying health parameters. As ketogenic diet is very high in fats, it is necessary to weigh the benefits by

achieving sugar control and weight loss versus. possible unfavorable effects on lipids and cardiovascular risk.Some may find ketogenic diet too rigid and expensive to follow on longer term. Thus, sustainability is an issue with this diet especially in vegetarians.

Mediterranean Diet

The Mediterranean diet has long been studied for its beneficial effects on heart health. This type of diet takes into account minimally processed grains and legumes as staple food, nuts - seeds and olive oil as a source of fats, using local and seasonal vegetables, fresh fruits, moderate consumption of low fat dairy and fish etc.

Regular physical activity is also a part of Mediterranean lifestyle. Along with the cardio-protective effects, this diet plays a great role in glycemic control due to anti­ inflammatory and antioxidant properties. Mediterranean diet is also known to improve gut microbiota. Avoidance of red meat, refined carbohydrates, saturated and trans fats contribute to improved insulin sensitivity.Several studies have shown that a traditional plant-based, regional Mediterranean diet prepared using healthy cooking methods coupled with physical activity can reduce your risk of physical as well as mental health problems.

Protects against Type 2 Diabetes

As the Mediterranean diet is rich in vegetables, nuts, whole grains (all good source of fibre) it slows digestion, prevents huge fluctuations in blood sugar and helps to keep sugar levels steady. Fibre also helps you maintain a healthy weight and reduces your waistline. It is effective in improved functioning of insulin.

Prevents heart disease and strokes

The Mediterranean diet limits your intake of unhealthy fats (saturated and trans fats) which are present in refined bread, processed foods and red meat. These contribute to heart disease. Instead, it encourages the intake of healthy fats like nuts and olive oil. This is the primary source of fat in the Mediterranean diet which is known to lower total cholesterol and LDL (bad) cholesterol levels.

Fish are also important in the Mediterranean diet. Fish rich in omega-3 fatty acids, a type of healthy fat that may reduce inflammation in the body, reduce blood clotting, help decrease triglycerides and decrease the risk of stroke and heart failure.

Promotes healthy weight management

Replacing simple carbohydrates by fibre-rich foods such as fruits, vegetables, whole grains and nuts gives you feeling of fullness and more satiated with which helps healthy weight loss and boost metabolism.

Apart from the above benefits, the Mediterranean Diet helps to reduce the risk of cancer,

• improves your gut health,

• reduces the risk of muscle weakness,

• reduces the risk of Alzheimer's and Parkinson's disease

Sustainability and complications

Mediterranean diet is more convenient to eat and less expensive than eating packaged or processed foods as meals are composed of mostly plants and whole grains. This diet can be followed by all irrespective of financial or socio-economic status.

Since the Mediterranean eating style encompasses eating healthy foods in moderation, there are very few risks associated with the Mediterranean diet.

• It is important to watch your weight. If you eat an excessive quantity of fats in oil and nuts you may put on weight. Consume recommended foods in moderation.

• You may have an inadequate amount of calcium by restricting the intake of dairy products. Take your health care provider's help for calcium supplementation, if needed.

• Though wine is a part of a Mediterranean eating style, avoid wine if you are prone to alcohol abuse, pregnant, lactating or have any medical condition that alcohol could worsen.

DASH diet

Originally Dietary Approach to Stop Hypertension  (DASH) eating pattern was meant for those with high blood pressure. DASH  diet encourages consumption  of foods high in potassium,  calcium, magnesium,  fiber, proteins and low in fats, cholesterol and sodium. This type of diet is practical,  easily adaptable to different styles of eating (vegetarian, vegan gluten free etc), does not require any special foods or supplements,  easy to follow and applicable for the entire family.

DASH diet focuses on an increased consumption of fruits, vegetables, whole grains, nuts and low fat dairy products. DASH diet should consist of the following foods:

Sustainability and complications

Long-term research studies have shown that DASH diet approach in hypertensive people  can lead up to 5.5 mmHg  reduction in systolic blood  pressure and 3 mmHg reduction in diastolic blood pressure. As DASH diet is high in potassium, phosphorus and protein, it is not advisable for individuals with end-stage renal disease.In addition to controlling blood pressure, this approach has also been shown to improve weight and insulin resistance.

People with Diabetes carry a higher risk of getting high blood  pressure than those without Diabetes. More than half of the adults with Diabetes have high blood pressure. Considering these facts, DASH diet offers double benefit of improved sugars as well  as blood  pressure.

Intermittent fasting

In intermittent fasting, meals are limited to a specific time window followed by fasting for fixed duration. Intermittent fasting may help with weight loss which in turn, improves blood  sugar control. Intermittent fasting does not advocate

omission or inclusion of any specific food group or nutrient. It simply modulates meal timings. There are different methods of intermittent fasting. Following are the common ones:

Time-restricted feeding   (TRF)                       

Eating for 8 hours, fasting for 16 hours. The easiest way to follow the 16:8 diet is to choose a 16-hour fasting window that includes the time that a person spends sleeping. Food should ideally be consumed by early evening, as metabolism slows down after this time. People usually choose an 8-hour eating windows like 9 a.m. to5 p.m. or 10 a.m. to 6 p.m. or noon to8 p.m. Within this timeframe, people can eat their meals and snacks at convenient times.

•  If you start eating at: 9 am, stop eating and start fasting at 5 pm.

•  If you start eating at: 11 am, stop eating and start fasting at 7 pm.

•  If you start eating at: 2 pm, stop eating and start fasting at 10 pm.

•  If you start eating at: 6 pm, stop eating

•  If you start eating at: 11 am, stop eating and start fasting at 7 pm.

•   If you start eating at: 2 pm, stop eating and start fasting at 10 pm.

•   If you start eating at: 6 pm, stop eating

Eating regularly is important to prevent blood sugar peaks and dips and to avoid excessive hunger.

Periodic prolonged fasting (PPF)

Fasting for 24 hours once or twice in a week. This is generally called 5:2 pattern

(5 days of normal eating, 2 days of fasting I

consuming only 500 to 600 calories per fasting day).

Alternate day fasting (ADF) Beginners can start gradually and increase the fasting window over a period of several weeks from 10 hours with aim to achieve 16 to 18

hours of fast per day.

In 5:2 or ADF pattern, fasting can be practiced once a week initially and when accustomed, it can be increased to twice or thrice a week. It gets easier over time. But consistency is the key.

Studies show that intermittent fasting initiates and accelerates weight loss. The mechanism is simple. Due to specific periods of fasting, total daily calorie consumption is reduced leading to weight loss. Whereas due to the metabolic shift, the body uses the fat as fuel resulting in fat loss.

Intermittent fasting leads to reduction in insulin secretion and increase in the secretion of growth hormone as well as norepinephrine. These hormonal changes aid fat loss. Further, fasting also triggers secretion of a protein called fasting induced adipose factor (FIAF) by liver and gut bacteria. FIAF also signals fat burning process.

Apart from weight and fat loss, intermittent fasting offers following health benefits:

• It is found to control blood sugar levels due to improved insulin sensitivity.

• As it increases resistance to stress, intermittent fasting improves longevity.

• It suppresses inflammation and oxidative stress.

• It improves blood pressure and blood cholesterol levels within 2 to 4 weeks. Intermittent fasting also improves resting heart rate.

• It improves memory and brain health, delays the onset and progression of Alzheimer's disease and Parkinson's disease (in animal models), improves cancer treatment, and improves immunity as well as longevity.

Sustainability and complications

While switching from regular or multiple meals diet to intermittent fasting, most of the people will experience symptoms like severe hunger, hyperacidity, headache, irritability, tiredness and lack of concentration. However, these initial symptoms fade away within a month. Other side effects include disturbed sleep pattern and overeating during feeding periods.It is also advisable to start intermittent fasting gradually over a period of several weeks.

T1me window for eating period can be gradually reduced and that of fasting period can be gradually increased. This helps the person cope up with hunger issues.

Intermittent fasting is not for those who are grossly underweight as it can lead to further weight and fat loss. Children, pregnant and breastfeeding women, endurance athletes should also avoid intermittent fasting.

These populations  have increased nutritional requirements and intermittent fasting can be restrictive.

Intermittent fasting has been found to be associated with eating disorders like bulimia nervosa. Therefore, those at risk of developing eating disorders (with family history of eating disorders etc) should avoid intermittent fasting.

Elderly, people taking treatment for Diabetes (insulin or oral hypoglycaemic agents) and those who are on any other medications need to be more careful while following intermittent fasting.

One must remember that any diet which involves long hours of fasting, poses a risk of hypoglycemia (low blood sugar) in people with Diabetes who are on medicines (like sulfonylureas) or insulin. On the contrary, there is possibility of hyperglycemia (high blood sugar) during

the eating window because of overeating due to excessive hunger.

Therefore, the dose and timing of medicine needs to be revised before initiating such a diet. Meals need to be planned meticulously. It is best to follow this diet under supervision of a doctor and a nutritionist at least in the initial phase.

To conclude

Apart from these five diets, diets like Paleo diet, Atkin's Diet, Vegan Diet are also popular among those with Diabetes. But one must remember that every Diabetes friendly diet has its own features and limitations too!Consider following points before you switch to any new dietary pattern.

•  Always choose a diet which can be followed for longer duration (short lived diets will offer benefits for short term only!)

•  It is always recommended to discuss with your Diabetes team (including doctors, nutritionists, exercise experts and educators) whether a particular diet will be suitable and medicines or insulin dose need any adjustments.

• Learn carbohydrate counting technique if you are on insulin and learn how to adjust your insulin dose based on pre meal sugar and carbohydrate content of the food.

• Check your blood sugar levels closely and systematically when you start with a new diet. This will help you know whether the new diet is offering anticipated benefits.

•   Involve family members in planning a new diet.

Remember - Diet is one of the cornerstones of Diabetes management. Other factors such as regular physical activity, stress management, adequate sleep, and compliance with the medicines are equally important. Don't neglect them!

Note: It is best practice to seek expert advice and consult your doctor and

dietician before starting or modifying eating patterns. If you have any health condition like Diabetes, hypertension, heart or kidney disease, etc. then routine health check-ups are recommended. These check-ups

should also check for nutritional deficiencies. Ensure that you undergo routine health check-ups to maintain your quality of life.

Speak with your doctor to find out if you can start or switch to a new diet plan. It is best to consult a registered dietician to understand the daily nutrient requirement to best suit your health parameters.

Dieticians can also provide guidance with food substitutes or supplements to suit your personal preferences and lifestyle.

If you are pregnant or planning a pregnancy it is best to consult a doctor prior to modifying your diet or changing eating patterns. For growing children and elderly consult a doctor and dietician before switching diets.

Dr. Tejas Limaye, M.Sc. Ph.D, RD, is a Clinical Nutritionist, Certified Diabetes Educator and the Joint Secretary, Pune chapter, Indian Dietetic Association (IDA)