Is feeling sick after sugar a red flag for diabetes?

In this article:

• How is sugar metabolized?
• Why do I feel sick after eating sugar?
• Is it diabetes?
• Managing sugar intake
• The bottom line

In this article

• How is sugar metabolized?
• Why do I feel sick after eating sugar?
• Is it diabetes?
• Managing sugar intake
• The bottom line

Indulging in sugary foods can feel great in the moment, but it can lead to some discomfort later on. Sometimes people experience bloating, abdominal pain, and nausea after too much sugar. But it’s important to know if that’s a normal reaction or the sign of a more serious condition like diabetes. Untreated diabetes can lead to a number of health problems. 

Understanding how your body processes sugar

When you eat carbohydrates, your digestive system breaks them down into sugars that enter your bloodstream. Rising blood sugar levels trigger your pancreas to release insulin, a hormone that helps your cells absorb and store sugar to use as energy. As levels drop again, another hormone called glucagon signals to your liver to release stored sugar to keep energy steady. 

Not all carbs act the same. Complex carbohydrates (natural sugars), such as those in vegetables and whole fruits, break down slowly, giving your body a steady stream of energy. Simple carbs, such as refined sugars, including table sugar and high-fructose corn syrup, digest quickly and can cause blood sugar spikes followed by a sharp crash. 

Over time, some people develop insulin resistance, when cells stop effectively responding to insulin, no longer storing sugars, and leaving blood levels high. This can lead to Type 2 diabetes, as the pancreas compensates by working harder to produce more insulin, and over time, those insulin-producing cells can wear out and stop working. Factors that contribute to insulin resistance include:

• Hormonal disorders, such as hypothyroidism
• Polycystic ovarian syndrome (PCOS)
• Pregnancy
• Genetics
• Excess body fat or obesity
• Lack of physical activity
• Diets high in processed foods, carbohydrates, and saturated fats
• Certain medications, such as steroids, antipsychotics, and HIV treatments

Chronically high blood sugar can cause complications such as nerve damage, vision loss, kidney problems, and gastroparesis, a slowing down of digestion that may lead to heartburn, nausea, vomiting, and the feeling of being “stuffed” or overly full, even after eating small meals. 

In severe cases, when the body can’t produce enough insulin, a very serious, life-threatening condition known as diabetic ketoacidosis (DKA) may develop. This is a medical emergency in which the liver breaks down fat to use for energy, producing dangerous levels of ketones. DKA is more common with Type 1 diabetes.

Why do I feel sick after eating sugar?

“Eating large amounts of sugary food such as candy, cake, or ice cream can cause your blood sugar to rise quickly. Your body responds to this sudden sugar spike by releasing insulin,” says Jennifer Warren, MD, a board-certified provider in obesity medicine and family medicine based in New Hampshire. “If that surge is high enough, the insulin response can sometimes overshoot, causing low blood sugar. That dip is what many people call a sugar crash.” 

Sometimes called reactive hypoglycemia or postprandial hypoglycemia, it’s what is responsible for those queasy feelings. You may feel tired, shaky, hungry, or irritable. It can trigger cravings for carbs or sweets as your body tries to quickly raise blood sugar. “The experience of a ‘crash’ varies from person to person, with individuals who have insulin resistance, prediabetes, or diabetes tend to have more dramatic fluctuations,” Dr. Warren adds.

True hypoglycemia occurs when your blood sugar remains low and is most common in people with diabetes, though it can sometimes happen in people without diabetes, too. Symptoms may include: 

• Sweating
• Lightheadedness
• Dizziness
• Shakiness
• Feeling anxious
• Rapid heartrate
• Headache
• Confusion

Some people can have a metabolic intolerance related to specific sugars (lactose, sucrose, and maltose) that can cause diarrhea and other gastrointestinal symptoms, though insulin problems are more common. 

When feeling sick after sugar might signal diabetes

 “Feeling bad after eating sugary foods isn’t, by itself, a sign of diabetes,” explains Dr. Warren. “Eating a lot of sugar will cause most everyone to feel poorly–nausea, feeling bloated, brain fog, and eventual fatigue,” adds Greg Whisman, MD, chief medical officer at CareMore Health in Columbus, Ohio.

Still, if you regularly feel sick after eating sweets, especially along with other symptoms, it may be time to talk with your healthcare provider.

According to the American Diabetes Association, the most common symptoms of diabetes include:

• Frequent urination
• Constant thirst
• Increased hunger, even after eating
• Extreme fatigue
• Blurred vision
• Slow healing of cuts, bruises, wounds, and infections

People with Type 1 diabetes may also notice unexplained weight loss, despite eating more, while those with Type 2 diabetes may also notice neuropathy—pain, numbness, or tingling in their hands and feet.  

If left untreated, diabetes can lead to serious complications. Persistently high blood glucose levels (hyperglycemia) can damage blood vessels and nerves over time, raising the risk of health issues, like eye disease (diabetic retinopathy), kidney problems, gum disease, skin infections, and heart disease. Illness and stress can also trigger or make hyperglycemia worse. 

Managing your sugar intake and feeling better

To avoid the uncomfortable sensations that may follow a sugar binge, Drs. Whisman and Warren recommend these lifestyle changes:

• Eat smaller portions over a longer period of time to avoid a blood sugar spike.
• Pair sugary foods with protein and high-fiber foods for a better balance. 
• Minimize sugary drinks such as soda, juice, coffee specialty drinks, and alcohol
• Stay hydrated to flush out extra sugar.
• Get some exercise. “Even a light walk may decrease that glucose spike,” Dr. Whisman says. 
• Seek medical advice or ask for an evaluation.
• Work with a dietitian or a nutritionist to design a personalized eating plan.

“If you have risk factors such as a family history of diabetes or obesity, you should ask your medical provider to perform a screening test,” Dr. Warren recommends. Several different tests can help diagnose diabetes, including the A1C test, the fasting plasma glucose (FPG) test, and the oral glucose tolerance test (OGTT). If you do have diabetes, your healthcare team will recommend a treatment plan, which may include dietary changes, physical activity, and insulin or other diabetes medications that can help you keep your blood sugar levels in your target range.  

The bottom line

Feeling sick after enjoying a sugar binge may make you regret your choices for a few hours, but it doesn’t necessarily mean that you have diabetes. It’s important not to jump to conclusions. However, if you notice that you always feel bad after eating or drinking a lot of carbs, it’s time to check in with a healthcare professional.