Fasting every other day to lose weight impairs the action of sugar-regulating hormone, insulin, which may increase diabetes risk, according to data presented in Barcelona at the European Society of Endocrinology annual meeting, ECE 2018. These findings suggest that fasting-based diets may be associated with long-term health risks and careful consideration should be made before starting such weight loss programmes.
Type-2 diabetes is a growing global epidemic that is often attributed to poor diet and a sedentary lifestyle, so is closely linked to obesity. Blood sugar is partially regulated by the hormone insulin, which is produced by the pancreas, if insulin levels are too low, or the body becomes resistant to its effects, type-2 diabetes results and high blood sugar levels can cause serious health issues, including heart, kidney and eye damage. In addition to medical strategies used to treat type-2 diabetes, patients are also advised to make lifestyle and dietary changes to lose weight. Recently, intermittent fasting diets have gained general popularity for weight loss, however, evidence on their success has been contradictory and there is a lack of knowledge and some debate on their potentially harmful long-term health effects. Previous research has also shown that short-term fasting can produce molecules called free radicals, which are highly reactive chemicals that can cause damage to the body at a cellular and may be associated with impaired organ function, cancer risk and accelerated aging.
In order to investigate whether an intermittent fasting diet could also generate damaging free radicals, Ana Bonassa and colleagues, from the University of Sao Paulo in Brazil, examined the effects of fasting every other day on the body weight, free radical levels and insulin function of normal, adult rats, over a 3-month period. Although the rats' body weight and food intake decreased as expected over the study period, the amount of fat tissue in their abdomen actually increased. Furthermore, the cells of the pancreas that release insulin showed damage, with the presence of increased levels of free radicals and markers of insulin resistance were also detected.
Ana Bonassa comments, "This is the first study to show that, despite weight loss, intermittent fasting diets may actually damage the pancreas and affect insulin function in normal healthy individuals, which could lead to diabetes and serious health issues."
The researchers now plan to investigate how this diet impairs pancreas and insulin function. There are many conflicting reports on the benefits and disadvantages, and many different types of intermittent fasting diets. Although these data were obtained in normal weight rats with positive effects on weight gain and food intake, the results suggest that in the long-term harm may be caused and that more investigation is needed to assess how people may be affected, particularly those with existing metabolic issues.
Ana cautions, "We should consider that overweight or obese people who opt for intermittent fasting diets may already have insulin resistance, so although this diet may lead to early, rapid weight loss, in the long-term there could be potentially serious damaging effects to their health, such as the development of type-2 diabetes."
FAQs
Could intermittent fasting diets increase diabetes risk? Fasting every other day impairs the action of sugar-regulating hormone, insulin, which may increase diabetes risk, according to data presented in Barcelona at the European Society of Endocrinology annual meeting, ECE 2018.
Does intermittent fasting increase diabetes risk? ›
Research shows intermittent fasting can lower your risk of diabetes and heart disease. “Type 2 diabetes is not necessarily a permanent, lifelong disease.
Can intermittent fasting cause blood sugar to rise? ›
Scientists know that insulin resistance improves with calorie restriction. After a period of fasting, insulin sensitivity increases and insulin levels decrease. These changes result in improved blood sugar levels both during fasting and shortly after eating.
Is 16:8 fasting good for diabetes? ›
There is also some new research that shows that fasting 16 hours of the day and eating within an 8-hour window might help you lower blood sugar levels and lose weight in the short-term. People have put their type 2 diabetes into remission following an intermittent fasting diet.
Does diet increase risk of diabetes? ›
Eating certain food can't cause type 2 diabetes. But there are some foods that increase your risk of developing type 2 diabetes including: Sugary drinks. Refined carbs like white bread, white rice and sugary breakfast cereal.
Can fasting too long raise blood sugar? ›
Fasting doesn't usually cause high blood sugar, but it's possible. If you already have diabetes, you may experience an early-morning increase in blood sugar, known as the dawn phenomenon.
Does fast food increase risk of diabetes? ›
Possible effects. Junk foods may contribute to diabetes in the following ways: Rapid effect on blood sugar levels: Highly processed foods that are high in calories and low in vitamins, minerals, and fiber break down quickly in the body and can cause a rapid rise in blood sugar levels.
Who should not do intermittent fasting? ›
Some people should steer clear of trying intermittent fasting: Children and teens under age 18. Women who are pregnant or breastfeeding. People with type 1 diabetes who take insulin.
Can fasting lower A1C? ›
Several case studies have shown a reduction in elevated hemoglobin A1c (HbA1c) levels in subjects after fasting, which some believe is due to sirtuin-6 (SIRT6) proteins. SIRT6 proteins are believed to be responsible for blood glucose homeostasis and insulin resistance reversal by increasing its sensitivity.
Why is my blood sugar high after fasting for 16 hours? ›
Since your body doesn't respond to insulin the same as most, your fasting blood sugar reading can go up, even if you follow a strict diet. The boost in sugar is your body's way of making sure you have enough energy to get up and start the day.
Fasting can be a practical way to lose weight because it's fairly straightforward, but it's not a mainstream treatment for type 2 diabetes. A very small study found therapeutic fasting -- going without food and drink with calories for a set amount of time -- can help reverse type 2 diabetes.
Does drinking water lower blood sugar? ›
Drinking plenty of water helps your kidneys flush out excess sugar. One study found that people who drink more water lower their risk for developing high blood sugar levels. And remember, water is the best. Sugary drinks elevate blood sugar by raising it even more.
What is the disadvantage of 16 8 fasting? ›
Potential Drawbacks of Intermittent Fasting
If you're not already used to skipping meals or not eating for an extended period of time, the hunger and fatigue that can occur when starting IF can be difficult to handle. Other side effects can include insomnia, irritability, headaches, and nausea.
What is the biggest contributor to diabetes? ›
Overweight, obesity, and physical inactivity
You are more likely to develop type 2 diabetes if you are not physically active and are overweight or have obesity. Extra weight sometimes causes insulin resistance and is common in people with type 2 diabetes. The location of body fat also makes a difference.
Can fasting diets cause diabetes? ›
Fasting every other day impairs the action of sugar-regulating hormone, insulin, which may increase diabetes risk, according to data presented in Barcelona at the European Society of Endocrinology annual meeting, ECE 2018.
What are 6 foods that can prevent diabetes? ›
3. Eat healthy plant foods
- Fruits, such as tomatoes, peppers and fruit from trees.
- Nonstarchy vegetables, such as leafy greens, broccoli and cauliflower.
- Legumes, such as beans, chickpeas and lentils.
- Whole grains, such as whole-wheat pasta and bread, whole-grain rice, whole oats, and quinoa.
4 tips to avoid sugar spikes
- There are specific measures for fasting blood sugar. ...
- Complex carbohydrates help control blood sugar. ...
- Exercise helps your body regulate blood sugar. ...
- Managing stress can help avoid blood sugar spikes.
Several case studies have shown a reduction in elevated hemoglobin A1c (HbA1c) levels in subjects after fasting, which some believe is due to sirtuin-6 (SIRT6) proteins. SIRT6 proteins are believed to be responsible for blood glucose homeostasis and insulin resistance reversal by increasing its sensitivity.
Is intermittent fasting bad for your pancreas? ›
“This is the first study to show that, despite weight loss, intermittent fasting diets may actually damage the pancreas and affect insulin function in normal healthy individuals, which could lead to diabetes and serious health issues.”
