How Can We Fight Insulin Resistance
Dr Thanh-Tam Pham - 7/3/2021
Insulin resistance is the root of many chronic diseases and over half of adults in the United States are affected without being aware of it. Dr Benjamin Bikman, in his book “Why We Get Sick”, gave scientifically proven strategies to improve insulin resistance.
The Importance of physical activity.
Even if a muscle is insulin resistant, it still can take glucose from the blood stream independent of insulin and after exercise the blood insulin naturally gets lowered. Exercise improves insulin sensitivity and also reduces central obesity, oxidative stress and inflammation. Regular and even light exercise can also improve sleep and may reduce markers of stress.
Exercise does not lead to significant weight loss but it makes muscles and bones stronger and better functioning heart and lungs.
- Aerobic versus resistance exercise:
There would be more improvements if you do both aerobic and resistance exercise than if you do either cardio or weight training alone.
- Intensity: individuals who are able to exercise more vigorously have greater improvements in insulin sensitivity. Many believe to take a glucose drink after the workout, but in doing so you lose some of the insulin –sensitizing improvements of the exercise. High intensity interval training like a brisk walk with intermittent sprints is more effective. As an individual becomes increasingly more trained, the body is able to predominantly use fat, rather than glucose, at higher and higher intensities.
- Cold exposure improves insulin sensitivity. Most of the fat in our body is “white fat” but there are smaller pockets of fat in the body that are brown as they are loaded with mitochondria. White fat wants to store fat and brown fat wants to burn fat to produce heat. At 18 degrees Celsius, brown adipose tissue becomes activated in men and women and starts burning glucose to warm the body. When temperature drops below this point, the body begins shivering which is more effective method of generating heat to maintain internal body temperature. Glucose is then consumed more rapidly and insulin secretion drops.
1- Limiting calories is the most common dietary intervention to prevent weight gain or aid weight loss and it is also used to fix insulin resistance. With calorie restriction, we have no control over where on the body, the weight loss occurs. It lowers the body fat but it also reduces the amount of lean mass especially muscle mass. With less muscle mass, there is less insulin –sensitive tissue available to clear glucose and restore insulin levels. Therefore calorie restriction can cause insulin resistance. People with anorexia nervosa are found to be less glucose tolerant and more insulin resistant than healthy lean individuals. “Fasting” has turned into “starvation” in this case.
Very low calorie diets cause stress on the body, with the increase of cortisol. Cortisol increases glucose and also makes the muscles and other tissue insulin resistant. Thyroid hormones are reduced to lower the metabolic rate and thus shift the body to an insulin resistant state.
Mild calorie restriction can improve insulin sensitivity.
- Dietary fibre:
Fibre improves insulin sensitivity especially soluble fibre generally from fruit and certain vegetables rather than insoluble fibre from grains and bran.
2- Intermittent fasting.
When we eat a meal, blood insulin rises to control glucose levels and elevated insulin is the most relevant factor in developing insulin resistance. Therefore frequent eating is not effective in controlling insulin.
Many of the benefits of fasting are caused by changes in hormones. Insulin drops quickly with a fast, and glucagon rises. While insulin tries to save energy in the body, glucagon wants to spend it by pushing fat cells to share their fat and the liver to share its glucose. Insulin and glucagon work against each other to activate and inhibit metabolic processes.
- Circadian rhythm and the Dawn phenomenon.
At the end of our sleep cycles in the morning at about 5:30 am, hormones such as catecholamines, growth hormones and cortisol act to increase blood glucose therefore insulin level starts to climb and begin falling within roughly 2 hours. The early morning high insulin indicates a mild insulin resistant state known as “the dawn phenomenon” or “dawn effect”.
Unlike the body as a whole, which is slightly more insulin resistant in the morning, our fat tissue is more sensitive in the morning and least sensitive in the evening. Because insulin inhibits fat burning and promotes fat cell growth, eating carbohydrates in the morning could add more fat compared with eating it in the evening.
3- Carbohydrate restriction.
Too much insulin is the driver of insulin resistance, so the obvious solution is to eat fewer carbohydrates. Dietary fat elicits no insulin effect at all.
A carbohydrate is good or bad is determined by its glycemic load or GL that is a number to estimate how much a particular carbohydrate will raise our blood glucose after we eat it. It is to differentiate with the glycemic index (GI), a measure of how quickly the carbohydrate is broken down into glucose in the blood.
A GL of 20 is “high”, 11 to 19 is “moderate” and 10 or below is “low”. High GL food includes sugary drinks, white pasta, bread, French fries, baked potatoes. Moderate GL foods are whole wheat pasta, brown rice, sweet potatoes, fruit juices with no added sugar. Low GL foods are kidney black beans, lentils, certain whole grain breads, cashews, peanuts and fibre rich vegetables and fruits
Watermelon has a high GI of 72 but GL is low at 2.
Most plant based food are lower in protein and fat and contain mostly carbohydrates with the obvious exceptions in “fatty fruits” such as avocado, olives and coconut.
Not everyone responds the same way to carbohydrate foods, GL is an estimated value but each individual glycemic response may vary. Differences in gut bacteria could explain how some people are able to readily use carbohydrates and others are not.
4- Saturated and polysaturated fats.
Contrary to what people usually think, animal fat like lard is not as bad as polyunsaturated fats in seed oils (vegetable, sunflower, canola, soybean oil…). The polyunsaturated fat (alpha-linolenic acid) in flaxseed oil improves insulin resistance.
The more unsaturated the fat is, the more it is easy to be oxidised and thus becomes harmful due to the presence of linoleic acid. Thus saturated fats from animal (meat, butter and ghee) and fruit sources (ie coconut, olive, avocado) are ideal.
The more saturated the fat, the more heat it can take. If you are cooking with the oil, use animal fats like lard and butter or coconut oil. If you are using oils for dressing, the monosaturated fats are ideal like olive, avocado oil.
- lowest carbohydrate: macadamia nuts, pecans
- moderate carbohydrate: most nuts including peanuts, almonds and walnuts.
- highest carbohydrate: pistachios, cashews
6- Micronutrients and vitamins.
- Magnesium: from leafy greens and nuts/seeds. Many studies showed Magnesium to improve insulin sensitivity.
- Vitamin D. People who are low in vitamin D have 30% higher risk of developing insulin resistance. The solution is to supplement vitamin D (4000iu) a day for a few months to improve insulin sensitivity to normal.
- Zinc: common in red meat and to a lesser degree in poultry. A study found 30mg of zinc/ day for 6 months improve insulin sensitivity while other studies do not confirm this.
- Chromium in green beans, broccoli, nuts, egg yolks. Taking chromium picolate 400ug/day for 6 weeks was found to improve insulin resistance.
- Calcium: some claimed calcium improve insulin sensitivity but in most studies they increased calcium to 1200mg/day by increasing dairy consumption so calcium by itself may not have that effect.
Why We Get Sick- by Dr Benjamin Bikman, PhD