Yes. Overeating drives type 2 diabetes. Excess calories, sugar and body fat make fat, liver and muscle cells stop responding correctly to insulin. That insulin resistance is the core of the disease.
We live in an age of convenience, where everything is available at the touch of a button. A study published in the Journal of Translational Medicine proves that obesity and Type 2 diabetes are even more closely linked to high-calorie diets than was first thought. The research found that overeating can tip your body into a pre-diabetic state in less than a week. This article sheds some light on some of our eating habits and how they might lead us down a path of chronic illness.
- Diabetes Mellitus and Diet
Diabetes exists in two forms: type-1 and type-2. The exact cause of type-1 diabetes is not known. Type-2, however, has been attributed to poor diet and a lack of exercise.
About 95% of all cases are type 2. In both types, there is excess glucose, or blood sugar, in the blood that the hormone insulin does not remove. In type-2 diabetics, insulin resistance develops. Fat, liver and muscle cells no longer respond correctly to insulin. Symptoms of type-2 diabetes can include fatigue, hunger, increased thirst, blurred vision, erectile dysfunction, increased urination, and slower healing. People diagnosed with type-2 diabetes are more likely to be overweight. That is because excess fat makes it harder for the body to use insulin correctly.
Diabetes mellitus (DM) was first recognized as a disease around 3000 years ago by the ancient Egyptians and Indians. They described some clinical features very similar to what we now know as diabetes. The name combines two words: “diabetes,” from the Greek for siphon, meaning to pass through, and the Latin “mellitus,” meaning honeyed or sweet. In 1776, excess sugar in blood and urine was first confirmed in Great Britain.
- What is the role of diet in T2DM?
In India, a startling observation was made. The disease was almost always confined to rich people who ate oil, flour, and sugar in excessive amounts. The First and Second World Wars further proved this. Records showed diabetes death rates declined due to food shortage and famines in the countries involved, such as Germany and other European countries. In Berlin, the diabetes death rate fell from 23.1/100,000 in 1914 to 10.9/100,000 in 1919. In contrast, there was no change in the diabetes death rate in other countries that did not have food shortage in the same period, such as Japan and North American countries.
Eating carbohydrates has been shown to increase the risk of developing T2DM. But sugar is a more harmful culprit. One study followed more than 500 ethnically diverse schoolchildren for 19 months. For each additional serving of carbonated drinks, the frequency of obesity increased. This held after adjusting for dietary, demographic, anthropometric (body measurement), and lifestyle factors.
Recent evidence suggests a link between soft drinks and obesity and diabetes. This is a result of the large amounts of high fructose corn syrup used to make these drinks. They have the potential to raise blood glucose levels and BMI to dangerous levels. It was also noted that diet soft drinks contain glycated chemicals that significantly boost insulin resistance.
There has been a strong link between food and obesity. Both the makeup and the amount of food matter here. High intake of sweets, fried foods and refined grains contributes to the increased risk of insulin resistance and T2DM. On the other hand, fruits and vegetables may protect against the development of T2DM. They are rich in nutrients, fiber, and antioxidants, which are considered a protective barrier against the diseases.
A recent study of Japanese women found that high intake of white rice was associated with a higher risk of T2DM. Dietary knowledge is a significant factor that influences eating behaviors.
- What then can we do to decrease our chances of getting diabetes?
- Avoid Fast Food
Several studies have shown that fast-food consumption can further the development of type-2 diabetes. A 2013 study published in the “European Journal of Nutrition” looked at overweight people. It set out to clarify the role of eating patterns in the onset of type-2 diabetes. It found that diets high in soft drinks and french fries, and low in fruit and vegetables, were associated with a greater risk of type-2 diabetes in overweight participants. This was particularly true among those who are less physically active. A 2005 study published in “Lancet” concluded that fast-food consumption has a strong positive correlation with weight gain and insulin resistance. This implies that fast-food intake may promote obesity and type-2 diabetes.
- Minimize Your Sugar Intake
High-sugar diets promote both weight gain and insulin resistance. This eventually leads to a susceptibility to type-2 diabetes. Also, having type-2 diabetes significantly increases the risk of developing Alzheimer’s disease. So changing your diet can greatly reduce the risk of both type-2 diabetes and Alzheimer’s disease.
- Note the quality of fats you use
To prevent type-2 diabetes, it may be more important to focus on the quality of the fats and carbohydrates you eat. High intakes of trans fatty acids, seed oils, refined carbohydrates, and other processed foods increase the risk for type-2 diabetes. In contrast, these foods can lower your risk: real olive oil, fiber-rich vegetables, omega-3 fatty acids from fish, and other minimally processed foods. Skip refined grains and seed oils. Red meat and fish are good protein for our patients.
- Eat inside your eating window, and stop snacking
When you eat matters as much as what you eat. Eat your meals inside a set eating window, and skip breakfast if it falls outside that window (see why we don’t count calories). Stop snacking between meals: a 2012 study in the “American Journal of Clinical Nutrition” found that snacking between meals raised type-2 diabetes risk.
- Increase Vitamin D intake
According to the National Institutes of Health, Vitamin D studies show a link. Having enough vitamin D in the blood is linked to being able to keep healthy blood glucose levels. Fish oils, trout, salmon, cheese, eggs, and mushrooms are all good sources of Vitamin D.
- Increase Your Activity
NIDDK studies show that insulin resistance goes down when you move more throughout the day. Try adding 30 minutes of walking, five days per week (that’s only five 6-minute walks each day at work).
- Do not Smoke
Ever. According to the CDC, smokers are 30-40 percent more likely to develop Type 2 diabetes than nonsmokers.
- Keep Your Waist in Check
According to NIH, a waist measurement of 40 inches or more for men is linked to insulin resistance. It also increases a person’s risk for Type 2 diabetes. This is true even if a person’s BMI falls within the normal range.
- Everybody’s responsibility
Type 2 diabetes is largely preventable with several simple steps. Keep your weight under control, exercise more, eat a healthy diet, and do not smoke. Yet it is clear that the burden of behavior change cannot fall entirely on individuals. Families, schools, worksites, healthcare providers, communities, media, the food industry, and government must work together. Together they must make healthy choices easy choices.
Frequently asked questions
Can you get diabetes from eating too much?
Yes. Eating more than your body can use drives type 2 diabetes. Research published in the Journal of Translational Medicine found that overeating can tip the body into a prediabetic state in less than a week. Excess calories, sugar and body fat make fat, liver and muscle cells stop responding correctly to insulin. That insulin resistance is the core of type 2 diabetes.
What is the number one cause of type 2 diabetes?
Insulin resistance, and the eating habits that create it. About 95% of diabetes cases are type 2, which traces to poor diet and too little movement. When fat, liver and muscle cells stop answering insulin, sugar stays in the blood instead of being cleared. Excess body fat makes insulin even harder to use. That is why people with type 2 diabetes are more often overweight.
Can overeating raise your blood sugar?
Yes. Diabetes is excess glucose in the blood that insulin fails to clear. High-sugar eating promotes both weight gain and insulin resistance, which leaves more sugar in the blood. Soft drinks sweetened with high fructose corn syrup can push blood glucose and BMI to dangerous levels. Diet sodas carry chemicals that significantly boost insulin resistance.
What is the worst food for your blood sugar?
Sugar, and sugar you drink most of all. Sugar does more harm than other carbohydrates. In a 19-month study of more than 500 schoolchildren, every extra serving of soda raised the rate of obesity. Fast food, fried foods and french fries round out the list. Studies tie them to weight gain and insulin resistance, the two steps that lead to type 2 diabetes.
Related reading
- How Much Sugar Can My Body Handle?
- Energy Balance Theory of Obesity
- Are Early-Life Antibiotics Harmful?
References
- NCBI (2017): Effect of diet on type 2 diabetes mellitus: A review. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5426415/
- Livestrong.com(2017): Can a Poor Diet Cause Diabetes? Retrieved from https://www.livestrong.com/article/445709-can-a-poor-diet-cause-diabetes/
- Men’s Journal (2019): Overeating Makes You Fat and Diabetic Faster than you Think. Retrieved from https://www.mensjournal.com/health-fitness/overeating-makes-you-fat-and-diabetic-faster-you-think/
- HSPH (2019): Simple Steps to Preventing Diabetes. Retrieved from https://www.hsph.harvard.edu/nutritionsource/disease-prevention/diabetes-prevention/preventing-diabetes-full-story/
Medically reviewed by Dr. Gurpreet Singh Padda, MD, MBA, MHP
Interventional pain physician, addiction medicine specialist and obesity medicine diplomate.
Licensed in Missouri and Illinois.
Last reviewed June 18, 2026
