Dietary choices can significantly impact skin health, with emerging research suggesting connections between food consumption and conditions such as acne and psoriasis. The glycaemic load of a diet—a measure of how quickly and how much a food raises blood sugar—appears to be a key factor in managing acne.
Studies have indicated that adhering to a lower glycaemic load diet can lead to a reduction in inflamed acne spots. This involves replacing refined carbohydrates and sugary foods, like sweetened cereals and pastries, with options such as whole grain bread and pasta, fruits, and protein-rich foods like lean meat, poultry, and fish. Research published in the American Journal of Clinical Nutrition in 2007 and Acta Dermato-Venereologica in 2012 reported significant decreases in acne severity among participants who adopted such diets.
The proposed mechanism involves insulin and IGF-1 (Insulin-like Growth Factor 1) levels. Foods with a high glycaemic load can rapidly increase insulin, which in turn may elevate IGF-1. This hormone can stimulate oil production in the skin and increase the multiplication of skin cells lining pores, potentially leading to blockages and bacterial growth, which results in inflamed spots.
While not yet formally included in treatment guidelines, individuals with severe acne might find it beneficial to focus meals on slower-release carbohydrates like oats, whole grains, and pulses, while minimizing consumption of sugary and fast-releasing foods such as pastries, biscuits, white bread, and chips.
Regarding dairy intake, an analysis of dietary habits involving nearly 80,000 young individuals, published in Nutrients in 2018, suggested a potential, albeit small and vague, link between milk consumption and acne. Consuming two or more glasses of milk daily was associated with more acne compared to lower intakes. Notably, skimmed and low-fat milk showed a stronger association than full-fat milk, possibly due to the milk proteins and sugars influencing insulin and IGF-1 levels. While milk is not definitively identified as a cause of acne, individuals with persistent spots who consume large amounts of milk might consider reducing their intake for six to eight weeks to observe any changes. It is important to ensure adequate calcium intake from alternative sources, such as fortified plant milks, if dairy is reduced.
For individuals with psoriasis, a condition characterized by an overactive immune system causing rapid skin cell reproduction, a Mediterranean-style diet may offer benefits. This diet, rich in olive oil, vegetables, and oily fish, is known for its anti-inflammatory properties. A small study in JAMA Dermatology found that patients with mild-to-moderate psoriasis who followed a Mediterranean diet alongside prescription creams experienced greater skin improvement compared to those on a general low-fat diet. Nearly half of the participants in the Mediterranean diet group saw a significant improvement in their psoriasis, while none in the comparison group did.
This dietary approach aligns with eating more vegetables, fruits, beans, whole grains, and fish, mirroring the principles of a lower glycaemic load diet.
Concerns about wrinkles and aging skin might lead some to consider collagen supplements. However, a review published in the American Journal of Medicine indicated that the perceived benefits of these supplements largely disappear when studies funded by collagen companies and lower-quality research are excluded. The body breaks down collagen from food sources, like bone broth or chicken skin, into amino acids before rebuilding its own collagen, which is used throughout the body, not exclusively for skin.
Conversely, the gut microbiome's fermentation of dietary fiber into compounds that can lower inflammation throughout the body, potentially including the skin, is a positive factor. Prioritizing vegetables, fruits, whole grains, beans, nuts, and seeds in the diet is suggested for long-term complexion benefits. Experts advise consulting a doctor or dermatologist before making significant dietary changes, especially if suspecting a specific food is contributing to a skin condition, and to remember that skin issues develop over time, not as an immediate result of a single meal.