Cutting back on sugar does more than affect body weight, according to a review of scientific evidence on diet and skin health. Researchers say the way the body processes glucose is linked to skin health, because blood sugar swings, inflammation and a process called glycation can all affect how skin functions.
The evidence, however, comes with a caveat: reducing sugar is not a cure for skin problems. It can, researchers say, form part of a broader, more balanced diet that supports the skin, but it is not a stand-alone treatment.
Fewer acne flare-ups
The link between diet and acne has been studied extensively, particularly around high glycemic load foods. Foods and drinks that cause a rapid rise in blood glucose can affect insulin and other metabolic pathways connected to inflammation and oil, or sebum, production.
The American Academy of Dermatology has said small clinical studies have shown fewer acne lesions in people who followed a low glycemic load diet. At the same time, the group has stressed that the available evidence is not entirely consistent and that more research is needed.
That means cutting back on sweets, sugary drinks and other foods that cause sharp glucose spikes could be a useful dietary change for some people with acne, though it does not replace proper dermatological treatment.
A steadier complexion
Sharp swings in glucose, and metabolic imbalances more broadly, have been linked to mechanisms that affect the skin barrier, the function of oil glands and the processes that rebuild tissue. Recent scientific literature considers these connections biologically plausible, though it notes that direct clinical data specifically tying sugar reduction to changes in skin appearance remains limited.
Improving the overall diet may therefore have a supportive effect on the skin, particularly when cutting sugar is paired with eating more vegetables, fruit, legumes, whole grains, nuts and enough protein.
The link between sugar and skin ageing
This is where glycation comes in, a process in which sugar molecules bind to proteins. Through a series of chemical reactions, this can create what are known as advanced glycation end products, or AGEs.
AGEs have been studied in relation to tissue ageing and the function of the extracellular matrix, the structure that houses key proteins such as collagen. Glycation is one of the biological mechanisms researchers have proposed to explain the link between glucose metabolism and the changes seen in tissue over time.
It is important to stress, though, that cutting out sweets will not make wrinkles disappear. Skin ageing is shaped by many factors, including age, genetics, UV exposure, smoking, sleep and overall diet.
Less sugar does not mean no sugar
A key point concerns what "reducing sugar" actually means in practice. The World Health Organization recommends that free sugars make up less than 10% of total daily energy intake, and says cutting that further, below 5%, may bring additional benefits. For a 2,000-calorie diet, 10% works out to roughly 50 grams of free sugars a day.
Free sugars include those added to foods and drinks, as well as sugars found naturally in honey, syrups and fruit juices. Natural sugars found inside whole fruit and vegetables are not treated the same way under these recommendations.
What to expect
Cutting back on excessive sugar consumption is a dietary change with multiple benefits for overall health, and it may have a supportive effect on skin as well. Of all the areas studied, the best-documented link involves high glycemic load and acne, while the connection between glycation and skin ageing remains mainly a biologically supported mechanism that scientists are continuing to study.
The goal, then, is not an extreme diet that eliminates sugar entirely. A more realistic approach is to limit added and free sugars, particularly from soft drinks, sweets and ultra-processed foods, and replace them with more nutritionally valuable foods. Skin is part of the wider body, and the quality of everyday diet is one of many factors that contribute to its long-term health.
