Diabetes has become more common in countries where food is plentiful. Excess sugar consumption can lead to obesity, cardiovascular disease, and other health problems. But can it cause diabetes?

The Centers for Disease Control and Prevention (CDC) estimate that over 37 million adults in the United States, or around 11.3% of the adult population, are living with diabetes. Another 96 million adults are living with prediabetes, putting them at risk of developing diabetes over time.

Dietary changes and exercise can help manage diabetes and may help prevent prediabetes from becoming diabetes. But does eating sugar increase the risk of diabetes?

Research into the connection between sugar consumption and type 2 diabetes is ongoing. Eating sugar alone may not lead directly to diabetes, but sugar may play a role. Diabetes is a complex condition that results from a range of factors.

This article looks at studies investigating the links between sugar consumption and the development of type 2 diabetes.

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Both type 1 and type 2 diabetes affect the body’s ability to regulate blood glucose levels.

Type 1 diabetes is an autoimmune condition in which the immune system attacks the cells that produce insulin. Damage to these cells undermines the body’s ability to manage blood glucose.

In type 2 diabetes, the insulin the body produces is unable to manage the glucose that enters the blood after eating or drinking.

Once a person has diabetes, eating too much sugar can make things worse. Added sugars are refined carbohydrates, and the body absorbs them quickly into the bloodstream. This can result in a blood sugar spike.

As the body either lacks insulin or cannot use it correctly, it will have difficulty transferring the glucose in the blood to the body’s cells. Levels of glucose in the blood will remain high.

Over time, high levels of blood glucose can cause damage throughout the body, and complications such as diabetic neuropathy can arise.

In addition, a high calorie intake can lead to weight gain and obesity. Obesity is a risk factor for type 2 diabetes.

Can you treat prediabetes through diet?

Eating sugar does not appear to cause diabetes directly, but it may play a role.

In 2016 some scientists noted a correlation between type 2 diabetes and lifestyle patterns that involve high consumption of sweetened drinks. However, while there is evidence that a high sugar intake can lead to weight gain, and a high BMI increases the risk of type 2 diabetes, there is no evidence that diabetes results directly from sugar intake.

The authors of a 2016 review suggested that a sugar called fructose may contribute directly to diabetes, although more research is needed to confirm this.

They noted that the liver absorbs fructose without regulating the intake. This could lead to a buildup of liver fats and a decrease in insulin sensitivity. Low insulin sensitivity makes it harder for the body to remove glucose from the bloodstream. If blood sugar becomes persistently high, type 2 diabetes can result.

Type 2 diabetes is one aspect of metabolic syndrome, which also encompasses obesity, cardiovascular disease, and other health conditions. In 2017, some scientists noted that dietary fructose may contribute not only to type 2 diabetes but to other aspects of metabolic syndrome, including obesity. They also pointed out that other factors would play a role, including genetics.

There seems to be a link between the overall consumption of foods containing added sugar and the incidence of type 2 diabetes. However, research has not shown that eating a lot of sugar will lead directly to diabetes. Precisely what forms the link between sugar and diabetes remains unclear and is likely part of a more complex process.

What does high blood sugar feel like?

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Many foods — such as fruits and some vegetables, such as carrots — naturally contain sugars. Others have sugar that people add at the table. Many foods contain hidden sugars that people might not expect to find.

For example, 100 grams (g) of ketchup may contain 21.8 g of sugar, including glucose, fructose, and maltose. A 12-ounce can of soda contains 10 teaspoons of sugar or 160 calories. Many processed foods that are high in sugar are low in useful nutrients, such as vitamins and minerals.

Sugars that people add to foods include:

  • table sugar (also called sucrose) that people put in drinks
  • caster sugar for use in baking
  • syrup, such as molasses or agave syrup
  • honey
  • molasses
  • cane sugar
  • corn sweetener
  • high fructose corn syrup
  • fruit juice concentrate

Foods that naturally contain sugars are:

  • fruits and some vegetables, which contain fructose
  • milk and dairy products, which contain lactose
  • juices and smoothies
  • oatmeal

Foods that contain added (and sometimes hidden) sugars include:

  • sweetened drinks, including sodas and energy drinks
  • candy
  • cakes, cookies, and other baked goods
  • many processed foods, including ketchup and ready meals
  • sweetened milks and yogurts
  • breakfast bars and cereals
  • ice cream
  • salad dressings

Check food labels in the store by looking not just for sugar content but also:

  • sucrose
  • glucose
  • fructose
  • lactose
  • maltose
  • galactose

These are all types of sugar.

People with diabetes should check with their doctor on how to account for different types of sugars in their daily carb count.

How much sugar is in your food and drink?

The American Heart Association (AHA) recommends the following maximum daily intakes of any type of added sugar:

For males9 teaspoons or 36 g or 150 calories
For females6 teaspoons or 25 g or 100 calories

One gram of sugar provides 4 calories. If a product contains 15 grams of sugar, it will provide 60 calories.

The World Health Organization recommends aiming for sugar to provide less than 10% of daily total calories.

Other tips for people with diabetes include:

  • Choosing carbohydrates with a low glycemic index (GI), such as whole grains.
  • Opt for whole fruit rather than sweetened snacks or juice, but remember to account for the sugar content.
  • Choosing fiber-rich foods, such as legumes, to provide sustainable energy and help manage blood glucose.
  • Opt for lean proteins and healthy fats to feel full for longer and reduce the temptation to have a sweet snack.
  • Avoid low nutrient, processed foods, which can be high in salt and unhealthy fats, as well as sugars.
  • Eat smaller meals more frequently. Large meals can cause blood sugar spikes and hunger between meals, which can lead to unhealthy snacking.

Discover some flavorsome, healthful dinner options for diabetes here.

Though the link between sugar and type 2 diabetes is uncertain, there is a clear link between sugar and other health conditions.

Health risks associated with a high sugar intake include:

  • a high body weight, which increases the risk of heart disease, some cancers, and type 2 diabetes
  • tooth decay
  • non-alcoholic-related fatty liver disease
  • cardiovascular disease
  • metabolic syndrome, which includes type 2 diabetes, obesity, and cardiovascular disease

High fructose corn syrup (HFCS) can lead to problems such as heart disease, obesity, diabetes, and non-alcoholic-related fatty liver disease, according to the National Institutes of Health. HFCS is present in many processed foods.

For these reasons, some experts have called for measures to help lower the amount of sugar children consume, such as changes in marketing strategies and a higher tax on products containing sugar.

What happens if you eat too much sugar?

Here are some questions people ask about sugar and diabetes.

Can I use artificial sweeteners with diabetes?

Artificial sweeteners are likely safe for people with diabetes, but experts do not know how they might impact blood glucose levels or cardiometabolic health in the long term. The American Diabetes Association advise people to choose sugar- and sweetener-free options where possible, for example, seltzer instead of sweetened soda.

Do natural sugars have the same effect?

Consuming too much of any sugar can lead to a glucose spike. People should check their blood sugar levels if they change their diet and ensure they keep them within the targets agreed with their healthcare team.

How much sugar can people with diabetes eat?

People with diabetes should follow the same guidelines as other people, that is a maximum of 9 teaspoons equivalent of sugar for males and 6 teaspoons for females. However, they should check that their total sugar intake agrees with the diet plan they prepare with their doctor.

While the link between sugar and diabetes is unclear, reducing added sugar and processed food in the diet can help a person prevent type 2 diabetes and its complications.

Genetic and environmental factors can contribute to the development of type 2 diabetes. If a person has genetic factors they may not be able to avoid type 2 diabetes, but they can take measures to reduce the risk.

Lifestyle choices that can help manage or reduce the risk of type 2 diabetes include:

Anyone who has concerns that they may be at risk of developing or having type 2 diabetes should speak with a doctor. The sooner a person receives a diagnosis, the better chance they have of managing blood sugar levels effectively and avoiding complications.

Scientists do not yet know what role sugar plays in the development of diabetes. Across populations, a higher sugar intake seems to correlate with higher rates of type 2 diabetes. However, it is not yet clear why this happens.

Sugar can increase the risk of other health problems, such as heart disease and tooth decay. The AHA and WHO advise people to limit their intake of all added sugars.

Ways of reducing the risk of developing type 2 diabetes include exercising regularly and eating a balanced diet that is high in fiber, protein, and saturated fats.

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