A 28-year-old overweight male presented to our weight management clinic for assistance with weight loss. The patient was minimally active and did not exercise. He had additionally been diagnosed with metabolic dysfunction-associated steatotic liver disease (MASLD).

He endorsed a 15-year history of acne vulgaris and had been following with dermatology. Physical exam demonstrated scattered facial comedones, erythematous papules and cysts with pitted scarring on the forehead (Figure 1) as well as pitted scarring with monomorphic, firm white papules on the upper chest and back. He had been to many dermatologists and had been treated with benzoyl peroxide 5% topical gel, amoxicillin, clarithromycin, clindamycin 1% topical lotion, doxycycline, and tretinoin 0.05% cream, with marginal improvement. The patient noted three years prior to presentation in our clinic, he temporarily put himself on an unsupervised “Keto Diet” and reported that his acne had significantly improved but then rebounded. Our clinical program includes collection of baseline history and physical exam as well as laboratory testing. We placed him on a ketogenic diet, with goal of <20 grams of carbohydrate per day until he achieved his goal weight or metabolic improvement. We also recommended a daily multivitamin and had him return for monthly visits to assess adherence and provide supportive counseling. We rely on patient reports to assess food intake (Table 1). After almost 8 weeks, he had lost seventeen pounds and experienced significant improvement in his acne (Figure 2). His waist circumference decreased by five inches (Table 2).

354138 Table 1.

354139 Table 2.

In this case, chronic cystic acne significantly improved with a ketogenic diet. Is the reduced acne secondary to the direct anti-inflammatory effects of ketosis? Could the improvement be due to the reversal of hyperinsulinemia or anti-androgenic effects of the ketogenic diet? Diets that result in increased production of both androgens and IGF-1 may correlate with increased sebum production, with low glycemic index or low overall glycemic load having the opposite effect.¹

A ketogenic diet requires near elimination of carbohydrates from the diet, with proportional increases in fat and protein to enter a state of ketosis, or state at which the body produces ketones for energy use.^2,3 The benefits are not limited to strict ketosis; low-carbohydrate diets of less than 50 or 100 g of carbohydrates per day could improve acne, as the relationship between acne and insulin secretion is well-established.^4,5 Lower carbohydrate intake reduces postprandial insulin secretion, decreasing adrenal androgen synthesis, leading to reduced androgen-induced sebaceous gland stimulation and sebum production.⁶ Additionally, the low circulating insulin levels caused by the ketogenic diet decrease hepatic IGF-1 production, decreasing sebocyte synthesis.⁷ The literature reports insulin resistance is significantly more prevalent in patients with acne vulgaris.^4,5

Higher body weight and body mass index (BMI) are associated with low-grade inflammatory states, marked by increased circulating inflammatory markers, including C-reactive protein, tumor necrosis factor a, and IL-6.² With the weight loss from ketogenic diets, these inflammatory markers decrease.² The ketogenic diet’s anti-inflammatory effect is also related to ketone production, specifically elevated Beta-hydroxybutyrate (BHB).⁸ BHB inhibits NLRP3 by preventing efflux of potassium ions, decreasing NLRP3 inflammasome complex’s ability to drive inflammatory responses, decreasing IL-1 and IL-18 production.⁹

In acne management, dietary counseling should be among first-line management strategies, specifically decreasing the amount of carbohydrates and excess sugar.³ While the role of diet in acne development and severity is controversial, the studied pathophysiology of acne due to diet aligns with the central theme of acne development; excess sebum production and increased inflammation. The pathway that leads to increased androgen hormones and insulin-like growth factor-1 (IGF-1) ultimately activates the mammalian target of rapamycin complex 1 (mTORC1), increasing sebaceous gland proliferation, lipid synthesis, and keratinocyte growth.¹ This pathway represents the pathophysiologic link between diet and acne, as dietary interventions such as the ketogenic diet have been shown to reduce mTORC1 signaling, thereby potentially mitigating these acne-promoting effects. Limiting dairy may also be worth considering because dairy intake has shown to activate mTORC1, along with IGF-1, and has been linked to worsening acne.¹⁰

The ketogenic diet is well-studied due to its utility in certain epileptic disorders, obesity, and type 2 diabetes; however, its impact is diverse. It can decrease liver function tests in patients with metabolic syndrome, hepatic steatosis and reversing MASLD.¹¹ As opposed to treatment with isotretinoin, a ketogenic diet tends to decrease hepatic triglyceride levels and improve hepatic insulin resistance, a main pathophysiologic driver of MASLD.¹¹ Ketogenic diets may cause keto-adaptation side effects of headache and fatigue, but these are generally mild and short-lived. Some individuals following a keto diet have an increase in cholesterol and LDL-cholesterol levels, but the significance of this effect in the context of an elevation in HDL-cholesterol and a reduction in triglyceride levels is not fully understood. The most commonly reported cutaneous side effect of the ketogenic diet is prurigo pigmentosa, which presents with reticulated pruritic erythematous papulovesicular on the trunk (Sun).¹²

While limited, evidence has shown that a ketogenic diet may positively impact depression and other mental health disorders.^13–15 Acne has been shown to have a strong relationship to depression, anxiety, decreased self-confidence, and suicidal ideation.^13,16 Researchers conducted a meta-analysis in 2021 which found that suicide was positively associated with acne in the total analysis.¹⁶ An additional study evaluating suicidality among children and adolescents with chronic skin disorders and found that 21% of those with acne attempted suicide and 33.9% had suicidal intentions.¹⁷ If a ketogenic diet may independently improve both acne vulgaris and mental health, it may improve both factors in some patients with these comorbidities. Additionally, while it is beyond the scope of this paper, the ketogenic diet may also benefit other inflammatory cutaneous disorders like hidradenitis suppurativa (HS), dissecting cellulitis, and psoriasis, warranting further investigation.

Evidence remains limited; dietary interventions are difficult to control and lack the funding that pharmaceutical trials receive. Further research is needed to delineate the relationship, but a low-carbohydrate diet represents a low-cost, low-risk intervention with potential benefits for patients with both metabolic dysfunction and acne.

Figure 1.

Figure 2.