The Basics: What Everyone Should Know
The ketogenic diet is very popular for weight loss and it can influence your skin in different ways. For some people it improves existing skin conditions, and for others it may trigger new concerns. If you are planning to start keto or are already following it, here is what you should know.
What Is Keto
Keto diet is a dietary practice with high fat intake and low protein and carb intake.
This means you often eat less than fifty grams of carbs in a day. When the body runs out of carbohydrates it shifts into a state called ketosis where it begins to use fat for energy and produces compounds called ketone bodies.
How Keto May Help Your Skin
Acne
Keto may help reduce acne by lowering insulin levels. Eating a lot of carbohydrates raises blood sugar and increases insulin. High insulin levels stimulate hormones that make the oil glands more active, leading to clogged pores and breakouts. When carbohydrates are kept very low, insulin levels also stay low. This reduces oil production and inflammation. A study by Verde et al., done in 31 women with acne, showed lower inflammatory markers after 45 days on a very low calorie ketogenic diet. [1]
Psoriasis
Keto may help calm psoriasis through its effect on inflammation. Weight loss plays a key role since excess weight increases inflammatory signals that worsen psoriasis. Ketone bodies also help reduce inflammatory chemicals that cause psoriatic plaques. In a study by Lambadiari et al., comparing the keto diet with the Mediterranean diet over 8 weeks, the keto group showed a clear reduction in psoriasis severity while the Mediterranean diet group did not. Another medically supervised keto program achieved 50% improvement within 4 weeks. [2]
Hidradenitis Suppurativa
This chronic condition causes painful, inflamed bumps in areas like the armpits or groin. Keto may help by reducing overall body weight and lowering inflammation. A small study by Verde et al. showed improvement in symptoms after twenty eight days on a ketogenic program. [3]
The Skin Problems Keto Can Cause
The Keto Rash
Some people develop an itchy red rash on the chest, back or neck about 2 to 4 weeks after starting keto. This is known as prurigo pigmentosa and it occurs due to a temporary rise in ketone bodies. After the bumps settle they may leave brown marks that take months to fade. The rash usually improves with certain medicines or by stopping the diet.
Vitamin and Mineral Deficiencies
Since keto restricts many food groups, deficiencies can develop and affect the skin.
Vitamin C is essential for collagen and wound healing. Low levels can cause bruising, bleeding gums and slow healing. There have been cases of children on long term keto developing scurvy due to lack of proper supplementation.
Biotin supports healthy hair and nails. Low biotin levels can lead to hair fall, brittle nails and a skin rash.
Zinc is needed for wound healing and immune function. Low zinc levels can cause red scaly patches near the mouth and eyes and may also lead to hair loss.
What You Should Do
It is best to consult a dermatologist and a nutritionist before starting the keto diet.
Daily supplements of vitamin C, biotin and zinc can be helpful.
Choose healthy fats such as olive oil, avocados, nuts and fatty fish rather than processed or heavy animal fats.
Watch for itchy bumps on the chest, back or neck during the first month.
Include plenty of vegetables such as leafy greens, broccoli, cauliflower and mushrooms to prevent deficiencies.
Give the diet at least four to eight weeks to observe changes in your skin.
Going Deeper: Understanding How It Works
If you want to understand the science behind keto's effects on skin, here's what's happening in your body.
The Insulin Connection
When you drastically cut carbs, insulin stays low. This triggers a hormonal chain reaction that's especially important for acne-prone skin:
Low insulin → Less IGF-1 hormone → More protective proteins (IGFBP-3 and SHBG) → Less free testosterone → Less DHT → Less sebum production → Fewer clogged pores
But there's more. Beta-hydroxybutyrate (the main ketone your body makes) blocks inflammatory pathways. It inhibits something called NLRP3, which reduces inflammatory molecules IL-1β and IL-18—both involved in acne inflammation.
The Antioxidant Effect
About 3 weeks into keto, your body adapts metabolically. This triggers a protein called Nrf2, which acts like a master switch for your skin's defenses. Nrf2 increases production of antioxidant enzymes that protect your skin cells from damage.
The diet also changes how cells produce energy, activating proteins called sirtuins. These proteins boost antioxidant defenses and block inflammatory pathways throughout your body.
The Gut Skin Connection
Keto changes your gut bacteria composition. It increases beneficial Bacteroidetes bacteria and decreases inflammatory Proteobacteria. These beneficial bacteria produce short chain fatty acids like butyrate, which have powerful anti inflammatory effects.
Butyrate strengthens your intestinal barrier and reduces inflammatory chemicals that can travel through your bloodstream to trigger skin inflammation. This gut skin connection may explain why keto helps inflammatory conditions like acne, psoriasis, and hidradenitis suppurativa.
What Studies Actually Show
The research is promising but limited. Most studies are small (under 50 people) and short term (4-12 weeks).
For psoriasis, in a study by Lambadiari et al., with 26 patients ,found keto reduced severity scores from 5.09 to 3.15 over 8 weeks, while Mediterranean diet showed no improvement.[2] Inflammatory markers IL-6, IL-17, and IL-23 all decreased with keto.
Another psoriasis study using very low-calorie ketogenic therapy (VLEKT - medically supervised, 650-800 calories daily) in 30 patients achieved 50% improvement in 4 weeks. IL-2 and IL-1β levels dropped.
For hidradenitis suppurativa, a pilot study with 12 women showed reduced severity after 28 days on VLEKT. They also saw decreased TMAO levels (a marker associated with HS severity).
The pattern is consistent: benefits appear around 4-8 weeks, not immediately. Medically supervised very low-calorie versions show stronger effects than standard keto.
Understanding the ‘Keto Rash’
Prurigo pigmentosa appears as itchy red bumps in a distinctive net like pattern, usually on the chest, back, or neck. It develops 2-4 weeks after starting keto and is triggered by ketone body accumulation.
Under a microscope, early lesions show neutrophilic inflammation, progressing to lymphocytic inflammation with pigment containing cells. This explains the persistent brown discolouration after healing.
Treatment is oral antibiotics daily. Stopping the diet also resolves it, though the hyperpigmentation may take months to fade.
Nutritional Deficiency Details
Vitamin C: Without enough, collagen synthesis fails. This causes poor wound healing, perifollicular hemorrhage (bleeding around hair follicles), and corkscrew hairs. Severe cases present as scurvy with bleeding gums, follicular hyperkeratosis, and petechiae. Multiple case reports document this in children on keto for epilepsy without supplements.
Biotin: Animal studies show keto increases biotin demand. One study found keto fed mice developed biotin deficiency symptoms by 5 weeks: seborrheic dermatitis like rash, alopecia, and decreased enzyme activity.
Zinc: Deficiency causes acrodermatitis enteropathica - well defined red plaques with erosions around the mouth, eyes, and genitals, plus hair loss. One documented case involved an 11-year-old on liquid keto formula who developed these symptoms. Zinc supplementation resolved everything within one month.
Why Fat Quality Matters
Not all fats affect inflammation equally. Unsaturated fats from olive oil, avocados, nuts, and fatty fish have anti inflammatory properties. Saturated fats don't offer the same benefits and may even increase inflammation.
The diet should include plenty of low carb vegetables (leafy greens, cruciferous vegetables, mushrooms) despite the carb restriction. These provide essential vitamins and minerals that supplements can't fully replace.
The Reality Check
Keto affects skin through multiple pathways: lowering insulin and oil production, decreasing inflammation, activating antioxidant defenses, and changing gut bacteria. The evidence suggests it may help acne, psoriasis, and hidradenitis suppurativa.
However, studies remain small and short term. We need larger, longer trials before considering keto a proven treatment for any skin condition.
Two main risks exist: the ‘keto rash’ that affects some people in the first month, and nutritional deficiencies if you don't supplement properly. The deficiencies can cause serious skin problems, from poor wound healing to actual scurvy.
And remember: keto isn't suitable for everyone.
If you are considering keto for skin health, work with healthcare professionals, take supplements daily, choose quality fats over processed ones, and monitor your response. Give it 2-3 months to see if it helps. If you are not seeing improvement by then, it may not be the right approach for you.
References
1. Verde et al., Very low-calorie ketogenic diet (VLCKD): a therapeutic nutritional tool for acne? J Transl Med. (2024).
2. Lambadiari et al., The effect of a ketogenic diet versus Mediterranean diet on clinical and biochemical markers of inflammation in patients with obesity and psoriatic arthritis: a randomized crossover trial. Int J Mol Sci. (2024).
3. Verde et al., Very low-calorie ketogenic diet (VLCKD) in the management of hidradenitis suppurativa (acne inversa): an effective and safe tool for improvement of the clinical severity of disease. Results of a pilot study. J Transl Med. (2024).
