“Health from eating” series | How much do you know about the impact of a high-sugar diet on your health?

Sugar is an important organic compound widely distributed in nature. The sucrose we eat daily, the starch in grains, the cellulose in plants, and the glucose in human blood are all sugars. Many foods are rich in sugars, including fruits, soda, bread, beans, potatoes, rice, and wheat. Sugar is a common energy source in organisms, but it is not a necessary nutrient for humans. The human body can also obtain energy from protein and fat. If the human body consumes a large amount of it, it will bring great harm to the body.

The amount of sugar your body needs each day varies depending on individual differences, age, gender, physical activity level and health status.

The Dietary Guidelines for Chinese Residents (2022) recommend: Control the intake of added sugars to no more than 50g per day, and it is best to control it below 25g.

High-sugar foods refer to foods that contain a lot of sugar, such as candy, cakes, desserts, soft drinks, etc. In addition, some fruits also contain high sugar, such as bananas, grapes, etc., but they also provide other important nutrients, so they are still considered healthy food choices. Overall, processed foods are the main source of people's high sugar intake.

Pastries and desserts: such as muffins, cookies, brownies, etc., normally contain between 10-30 grams of sugar, depending on the type and size of the food.

Carbonated drinks: A 600 ml bottle of Coke contains about 60 grams of sugar.

Candy: For example, hard candy, chocolate, chewing gum, etc., its normal sugar content will also vary depending on the brand and type. The sugar content of a hard candy may be between 4-6 grams.

Jams and marmalade products: One tablespoon of jam typically contains 12 grams of sugar.

Sweet drinks and fruit juices: A typical 200ml can of sweet drink may contain about 40g of sugar.

Excessive intake of high-sugar foods may cause the following harms:

Excessive intake of high-sugar foods may be associated with mental health problems. Studies have found a link between a high-sugar diet and mental illnesses such as depression, anxiety, and attention deficit hyperactivity disorder (ADHD). High sugar intake may affect the balance of neurotransmitters and increase the risk of mental illness.

Increased risk of metabolic syndrome: Metabolic syndrome is a group of symptoms associated with an increased risk of cardiovascular disease and diabetes. Excessive intake of high-sugar foods may lead to insulin resistance, hypertension, and lipid metabolism disorders, thereby increasing the risk of metabolic syndrome.

Addiction: Foods high in sugar can be addictive for some people. Excessive intake of high-sugar foods may cause the body to become dependent on sugar, making it more difficult to resist appetite and causing cravings. This addiction may lead to continued high sugar intake and increase the risk of obesity and related health problems.

Increased risk of breast cancer: Some studies have found that excessive intake of high-sugar foods may be associated with an increased risk of breast cancer. A high-sugar diet may promote the occurrence and development of breast cancer by promoting chronic inflammation and affecting hormone levels.

Increased risk of cardiovascular disease: Excessive intake of high-sugar foods can lead to drastic fluctuations in blood sugar levels and insulin levels, which may increase the risk of cardiovascular diseases such as heart disease and stroke.

Damage to intestinal health: When high-sugar foods are digested, they are quickly fermented by harmful bacteria in the intestines, producing a large number of harmful metabolites. These metabolites may irritate the intestinal mucosa, cause intestinal inflammation and intestinal microecological imbalance, and increase the risk of enteritis, gastrointestinal diseases and intestinal infections.

Reduced immunity: The intake of high-sugar foods can weaken the function of the immune system, making the body more susceptible to infection and disease.

Aggravation of inflammatory diseases: High sugar intake may induce or aggravate some inflammatory diseases, such as arthritis, inflammatory bowel disease, and autoimmune diseases. This is related to the inflammatory response and decreased immune function caused by high sugar intake.

Impairment of memory and cognitive abilities: A high-sugar diet may have a negative impact on the brain’s memory and cognitive functions. Excessive intake of high-sugar foods can lead to inflammation and insulin resistance, which may damage the function of brain neurons and increase the risk of Alzheimer’s disease and cognitive impairment.

Accelerate skin aging: Excessive intake of high-sugar foods can cause glycation reactions, which can cause glycation of proteins, collagen, and elastic fibers in the body. This can lead to a loss of skin elasticity, the formation of fine lines and wrinkles, and accelerate the skin aging process.

Impact on sleep quality: Excessive intake of high-sugar foods can cause dramatic fluctuations in blood sugar, which may lead to poor sleep quality. The energy crash and unstable mood caused by blood sugar fluctuations may interfere with the process of falling asleep and staying asleep, leading to insomnia and poor sleep quality.

The above are some of the potential hazards of high-sugar foods, but it should be noted that not all high-sugar foods have the same hazards. The key lies in the amount and frequency of intake. Reasonable control of the intake of high-sugar foods and strengthening a nutritionally balanced diet can help reduce the impact of these hazards on health.

In short, limiting sugar intake helps to stay healthy. The World Health Organization recommends controlling sugar intake and limiting it to less than 10% of total energy intake, especially limiting the intake of added sugars. Moderate intake of natural sugars naturally found in fruits, vegetables and dairy products is a healthy choice. For individual specific sugar intake limits and other dietary advice, it is best to consult a doctor or professional nutritionist.

This article was scientifically reviewed by Xin Xiaowei, nutritionist and deputy director of the Nutrition Department of the Cancer Hospital, Chinese Academy of Medical Sciences.