Why does eating sugar make me sweat?

Dear Candy Lover, 

The short and sweet answer to your question is that you might be having an insulin reaction to sugar, or what’s more commonly known as a “sugar crash”. Based on what you’ve described, it’s hard to tell whether your sticky situation is due to the type of sugar you’re eating or another condition like sugar intolerance or reactive hypoglycemia (more on these later). However, understanding potential causes can help you decide whether to speak with a medical professional about your symptoms and may offer useful steps to keep the sugary sweats at bay. 

Some things that can cause people to work up a sweat after eating sugary foods include: 

• Sugar intolerance: Some people have difficulty digesting certain types of sugar like fructose (found in fruits, vegetables, and honey) and lactose (found in dairy products). Common signs of sugar intolerance often include stomach cramps, abdominal discomfort and bloating, and headaches. However, symptoms can vary widely from person to person. 
• Gustatory hyperhidrosis: Sometimes known as Frey Syndrome, this condition can cause excessive sweating of the face, scalp, and neck during or after eating. It may be associated with diabetes, nervous system disorders, and other conditions. 
• Reactive hypoglycemia: Reactive hypoglycemia occurs when there’s a drop in blood sugar levels after eating. Symptoms include weakness, sweating, rapid heartbeat, and lightheadedness. As episodes are often triggered by eating high-carbohydrate foods, one explanation is that the body produces insulin to lower blood glucose levels after eating but doesn’t produce enough glucagon to offset the insulin. Without sufficient glucagon, the body can’t bring the blood sugar level up after it goes down, leading to a “sugar crash”. 

You mentioned that chocolate and hard candies make you break out into a sweat, but cane sugar doesn’t. One reason why these sugary confections might be the culprit in your clammy conundrum is because of their high glycemic load. Glycemic load (GL) is a ranking system that considers both the glycemic index of a particular food and the total amount of carbohydrates per serving to estimate how quickly it raises blood glucose levels, and for how long. Because processed confectionery products like chocolate and candy have much higher glycemic load values than pure cane sugar, they can cause blood sugar levels to spike and fall more rapidly, leading to the symptoms you describe. Some people may also be sensitive to certain additives in food. Is it possible that you’re reacting to something besides the sugar in candy and chocolate? Do you notice any other differences between the foods that affect you and those that don’t? 

Although what you eat can affect how you feel, it may also be helpful to consider when and why you might be reaching for these sugary snacks. Does the pantry look more inviting in the evening? Do you find yourself craving foods that pack a sugar punch when you’re feeling stressed? Some factors that can intensify a “sugar crash” or mimic the symptoms that you’re experiencing include: 

• Stress: Stressful situations can induce an adrenaline rush, or what’s commonly known as a “fight or flight” response. Adrenaline is a hormone that primes the body for action in response to a perceived threat. It may cause rapid heartbeat, sweating, and shaking. Stress can also indirectly cause blood sugar levels to spike and crash. The “fight or flight” hormones that flood the body provide a burst of energy by releasing stored glucose into the bloodstream, causing blood sugar levels to rise. Long-term stress due to prolonged stressful conditions can also affect blood sugar. Elevated levels of cortisol, a stress hormone, can intensify sugar cravings and the motivation to eat. 
• Meal timing: Blood glucose levels tend to rise more and remain high for a longer time after eating in the evening compared to the morning. 
• Sleep quality: Heading to bed later than usual and having poor sleep is associated with a steeper spike and fall in blood sugar levels the next morning. 

The good news is there are some steps you might take to flatten the blood sugar curve and reduce discomfort. These include eating meals with a lower carbohydrate and higher protein and fat content, reaching for fruit instead of sweets for dessert or a snack, and eating smaller but more frequent meals throughout the day. The American Heart Association recommends that individuals assigned male at birth limit their daily intake of added sugar to nine teaspoons (150 calories) and individuals assigned female at birth consume no more than six teaspoons (100 calories) of added sugar daily. 

Although a post-sugar dip is usually nothing to sweat about, it’s recommended that you speak with a health care provider if you experience recurring symptoms. They may be able to do additional tests to rule out an underlying medical condition and suggest diet and lifestyle modifications to help you manage your condition. If you decide to speak with a health care provider, it’s helpful to discuss your symptoms, how long these symptoms last after eating, specific foods that trigger sweating, and any other health conditions that you may have. 

Here’s to finding that sweet—not sweat—spot!