The science behind type 2 diabetes reversal

Type 2 diabetes is popularly known as a chronic progressive disease that gets worse over time and often leads to complications and eventual death. It is believed that people living with type 2 diabetes have to be on lifelong medication. This used to be true until now. In this essay, I will be showing you that type 2 diabetes is a reversible condition and that people can go off medications.

I’ll start by helping you understand what type 2 diabetes really is. Type 2 diabetes is characterized by a high amount of glucose in the blood. It is commonly thought to occur either because cells in the body are not responding to insulin (insulin resistance) or because there is a reduction in the amount of insulin produced by the beta cells of the pancreas or a combination of both.

Insulin is a hormone produced by beta cells in the pancreas. It has many functions, like allowing the glucose in the blood to go into cells thereby reducing the amount of glucose in the blood or inhibiting protein breakdown in muscle cells, and fat breakdown in fat cells. In this essay, I’ll be focusing on its effect on glucose.

Understanding insulin resistance

Insulin resistance is basically a problem of faulty insulin signaling plus elevated insulin levels (hyperinsulinemia). Insulin resistance in different cells manifests in different ways. I will write an essay on it in the future. When we eat, carbohydrates are broken down into simple sugars (mostly glucose and fructose). Most cells need insulin to be able to take in the glucose from our blood. When the insulin signaling is compromised as in the case of insulin resistance, the glucose remains in the blood, hence the high blood sugar. Insulin resistance is caused by 3 things — hyperinsulinemia, Inflammation, and high cortisol levels (stress). I’ll leave it at this because it is out of the scope of this essay.

Understanding beta-cell failure

It is commonly thought that the reduction in insulin production that happens in some patients is because the beta-cells are “burnt out” — ie. dead. This is not true. There is research showing that the beta-cells “fail” because they are clogged with fat. This fat comes from the excess fat in the liver. “Failure” doesn’t mean death. Heart failure occurs when the heart muscle doesn’t pump blood as well as it should. It doesn’t mean the heart is dead. So I suggest that people use the term “beta-cell failure” instead of saying beta cells are burnt out. Certain therapeutic interventions that remove the fat from the pancreas cause the beta cells to become active again[1] (this term is called beta-cell reversal. If the beta cells were burnt out, we would not have an increase in insulin production. Dead cells don’t come back to life).

Introducing type 2 diabetes reversal

Type 2 diabetes is just an arbitrary point on the metabolic health spectrum. This means you can either move to the left (ie. get healthier) or move to the right (ie. get worse and develop complications). Everyone is born on the left and due to diet and lifestyle, we move towards the right. To reverse type 2 diabetes, we need to think about things that can move people who are on the right side to the left side.

The American Diabetes Association defines type 2 diabetes reversal as a return of HbA1c to less than 6.5% that occurs spontaneously or following an intervention and that persists for at least three months in the absence of usual glucose-lowering pharmacotherapy

How to reverse type 2 diabetes

The central idea of reversing type 2 diabetes is lowering the need for insulin and improving insulin sensitivity. In cases of anti-microbial resistance, you don’t increase the antibiotic dosage. If you do that, you’ll be doing more harm. In the same light, To treat insulin resistance, you need to reduce the body’s need for insulin. This is one of the reasons why treating type 2 diabetes with exogenous insulin doesn’t lead to improved outcomes[2]. Any intervention that reduces the body’s need to produce insulin has the potential to address insulin resistance and invariably, type 2 diabetes. There are 3 verified ways to reverse type 2 diabetes.

Bariatric surgery

Bariatric surgery refers to a group of surgeries that makes changes to one’s digestive system. It is typically a weight loss surgery but it also has an effect on blood sugar control. It is a surgery that reduces the size of the stomach which reduces the amount of food one can eat. It also causes hormonal changes that help reduce hunger and increase the feeling of fullness. This means that people that undergo bariatric surgery tend to eat very little enough to raise their blood sugar, so their body’s need for insulin drops. One long-term study tracked 400 people with type 2 diabetes. Six years after bariatric surgery, 62% showed no signs of diabetes[3].

Very low calorie diets

A low-calorie diet is made up of around 800 to 1,200 calories a day. For reference, the average person eats between 2,500–3,000 calories per day. Low calorie diets also work by extremely limiting the amount of food a person eats daily. Therefore blood sugar does not go up and there’s little need for the body to produce insulin. Low calorie diets reduce abdominal fat, including fat in the pancreas. This allows the pancreas to get back to normal insulin production. Low calorie diets implemented in a medical, scientific, and real-world setting have resulted in remission rates as high as 46% at one year[4]. The disadvantage of this method is that it causes a person to be hungry most of the time, and in many cases, it is not sustainable. In one study, only 7% achieved remission after 4 years of an initial low calorie formula diet replacement, followed by a calorie and fat-restricted nutrition therapy with physical activity[5].

Low carbohydrate diets

Low carbohydrate diets are diets that restrict the amount of carbs that a person eats. In low carbohydrate diets, there’s an emphasis on replacing starchy carbs and refined sugars with low carbohydrate vegetables. So this diet doesn’t necessarily affect the size of food a person eats. Carbohydrates directly raise blood sugar and it has the most demand for insulin production. It is very easy to see how carbohydrate restriction would lead to reduced blood sugar and reduced insulin demand and this helps to improve insulin sensitivity. Insulin levels direct fuel use in the body. High insulin levels promote fat storage and lower level promote fat burning. Fat burning help to resolve things like fatty liver and reduce abdominal fat, including fat in the pancreas. This allows the pancreas to get back to normal insulin production. A low carbohydrate diet is the most sustainable nutrition-based method for most people. This study shows the long-term impact of a low carbohydrate diet with 25% of patients achieving remission after 2 years[6]. Virta Health, a company that uses low carbohydrate nutrition to reverse type 2 diabetes, recently shared their 5-year clinical trial result that showed that 20% of their patients acheived type 2 diabetes remission at 5 years.

I think it is important to inform patients that reversal or remission doesn’t mean “cure”. If they return to their previous unhealthy habits the disease might come back. Patients should also be advised to see their doctors regularly for ongoing support and to prevent a relapse. David Sackett, the father of evidence-based medicine once famously said:” half of what you’ll learn in medical school will be shown to be either dead wrong or out of date within five years of your graduation; the trouble is that nobody can tell you which half — so the most important thing to learn is how to learn on your own.” This is why it is important to keep up with research. The knowledge and treatment of type 2 diabetes have improved in the last 10 years. It is important to embrace these changes so that we can offer the best treatments to our patients.

References

1. Taylor R. Banting Memorial lecture 2012: reversing the twin cycles of type 2 diabetes. Diabet Med. 2013;30(3):267–275. doi:10.1111/dme.12039
2. Erpeldinger S, Rehman MB, Berkhout C, et al. Efficacy and safety of insulin in type 2 diabetes: meta-analysis of randomised controlled trials. BMC Endocr Disord. 2016;16(1):39. Published 2016 Jul 8. doi:10.1186/s12902–016–0120-z
3. Adams TD, Davidson LE, Litwin SE, et al. Health benefits of gastric bypass surgery after 6 years. JAMA. 2012;308(11):1122–1131. doi:10.1001/2012.jama.11164
4. Lean MEJ, Leslie WS, Barnes AC, et al. Durability of a primary care-led weight-management intervention for remission of type 2 diabetes: 2-year results of the DiRECT open-label, cluster-randomised trial. Lancet Diabetes Endocrinol. 2019;7(5):344–355. doi:10.1016/S2213–8587(19)30068–3
5. Gregg EW, Chen H, Wagenknecht LE, et al. Association of an intensive lifestyle intervention with remission of type 2 diabetes. JAMA. 2012;308(23):2489–2496. doi:10.1001/jama.2012.67929
6. Adams RN, Athinarayanan SJ, McKenzie AL, et al. Depressive symptoms improve over 2 years of type 2 diabetes treatment via a digital continuous remote care intervention focused on carbohydrate restriction. J Behav Med. 2022;45(3):416–427. doi:10.1007/s10865–021–00272–4