Fact-checked by Dr. Anthony Gustin, DC, MS.
Written by Emily Ziedman
Acne is like your body’s warning sign that there’s something wrong inside your body.
Besides being uncomfortable and sometimes embarrassing, severe acne breakouts are psychologically stressful and can take a toll on emotional health as well[*].
Acne can hit at any age. And that’s because there are several leading causes of acne, from hormonal to genetic, to dietary components like chronic high blood sugar and insulin levels.
If you’re looking for ways to bust acne and boost skin health, read on. There’s good scientific evidence that diet affects acne and that changing up your food choices could be the biggest step you make in treating this annoying and painful skin condition.
Acne (also known as acne vulgaris) is the most common skin disorder in the United States, with up to 50 million Americans affected each year. In fact, at least 85% of people between 12 and 24 experience acne.
Although you may think that acne is a condition reserved for teenagers, it can actually affect you well into adulthood and is becoming more common in adult women[*].
Here’s a little breakdown of how acne forms:
Acne affects the oil glands in your skin. These glands, also known as sebaceous glands, secrete an oily substance called sebum. Sebum is made up of fatty acids, cholesterol, and a compound called squalene and is secreted to keep your skin and hair moist and protected.
There are sebaceous glands everywhere that you have skin, except your hands and feet. Different areas of your body have varying amounts of these glands, but your forehead and chin have the most.
Tiny holes in your skin, called pores, connect to your sebaceous glands through small canals called follicles. Then sebum emerges from your pores to coat your skin.
All these aspects of your skin; sebaceous glands, sebum, follicles, and pores work together to make sure your skin stays hydrated and healthy.
However, the system doesn’t always work optimally, and your hair, sebum, and skin cells can end up clumping together and forming a plug. When this happens, bacteria in the plug can cause swelling, which turns into a pimple — otherwise known acne.
Most people experience acne on the face, neck, back, chest and shoulder — areas where you have the most sebaceous glands[*].
Aside from a buildup of dead skin cells and sebum, the root cause of acne is still unknown. There are, however, several factors that can contribute to acne, including:
#1 Genetic Predisposition
Genetics is an important factor to consider in the development of acne. One study of 200 participants with adult acne found that 50% of the patients had at least one first-degree relative with acne[*].
Another study collected data from more than 5000 undergrad students to assess the risk factors for the onset of acne. Among the top risk factors were first degree and second-degree relatives with acne.
Heritability of acne was nearly 80% for students with a first-degree relative that had acne[*].
#2 Androgen Hormones
Androgens are steroid hormones that are responsible for traits typically associated with men, like underarm hair and muscle mass.
Although these hormones responsible for male traits, everybody has androgens — testosterone being the most well-known.
An excess of androgens can cause an increase in sebum secretion, which can clog your pores and cause acne[*].
This is a huge reason that you see a rise in acne breakouts during puberty — a natural surge in androgens.
Androgens in males can cause changes in body composition and hair growth, and in females, they typically convert to estrogen to increase female-like characteristics[*]. And both sexes are subject to a rise in acne breakouts.
Although hormonal acne is most common in pubescent adolescents, androgen-mediated acne can happen at any stage of life where there’s a hormone imbalance.
One common cause of adult acne in women is PCOS (polycystic ovarian syndrome), a condition that typically develops around child-bearing years.
With PCOS, women experience higher levels of androgens than normal, throwing off their sex hormones and leading to a host of physical issues — acne being one of them[*].
#3 Insulin-Like Growth Factor Hormone
Another hormone, insulin-like growth factor (IGF1), also increases during puberty and may contribute to the onset of acne.
But there’s also a chance that higher IGF-1 is responsible for an increase in sebum production and inflammation, which can contribute to acne[*].
You’re probably well aware of the impact that stress can have on your body. Too much stimulation and worry can leave you feeling depleted, foggy-headed, and tired — and it may also contribute to your breakouts.
Your skin has an intimate relationship with your nervous system and stress response.
When you’re emotionally stressed, the nerves in your skin can release neurotransmitter-like compounds which cause an increase in pro-inflammatory chemicals. These chemicals induce inflammation in your skin and may contribute to acne[*].
“While the research is fairly new, it seems like there’s a strong link between stress and breakouts[*].
Diet and gut health can play a significant role in the development and management of acne.
Although everyone’s body is different, certain foods that trigger acne more consistently than others.
Here are a few dietary influences that you should know about if you’re fighting the acne battle.
#1 Processed Carbohydrates And Sugar
Foods with a high glycemic index are foods that cause your blood sugar to rise quickly. The measure of a food’s glycemic index, plus the amount of the food you consume makes up the glycemic load of that meal.
The more your blood sugar rises, the higher the glycemic load. And there’s some evidence that a high glycemic diet may contribute to the progression of acne[*].
When you eat foods that increase your blood glucose, an increase in the hormone insulin follows. High insulin levels increase your levels of IGF-1 as well as androgens, two hormones that can lead to excess sebum production and the buildup of tissues that cause acne[*].
Insulin may also reduce proteins that bind androgens and IGF-1, which means higher concentrations of these acne-causing hormones in your body[*].
In contrast, a low-glycemic diet can improve acne[*].
In one study, researchers gave 32 patients with mild to moderate acne either a low-glycemic diet or a control diet for 10 weeks. At the end of the trial period, they found that the low-glycemic group significantly improved both inflammatory and non-inflammatory acne lesions, reduced the size of their sebaceous glands, and decreased overall inflammation[*].
Many people anecdotally report clearer skin when they remove dairy from their diet. And research shows a positive correlation between dairy intake and incidence of acne — especially in adolescents[*][*].
Milk and milk products can increase your IGF-1 levels, which can activate androgen signaling and subsequent increases in sebum production[*]. This, along with the inflammatory effects of IGF-1 may cause breakouts[*].
Dairy milk also contains many growth-promoting hormones on its own. It makes sense — dairy is meant to increase the growth of calves. But these hormones aren’t specific to baby cows and can alter your hormone activity[*].
Many dairy cows in the United States are also treated with bovine growth hormone to increase their milk supply. Bovine growth hormone can increase your levels of IGF-1 further, which would result in increased sebum production[*].
If you do consume dairy, make sure it’s in moderation and avoid any dairy with bovine growth hormone.
#3 Omega-6 Fatty Acids
Inflammation is one of the primary aspects of acne. In fact, some sources suggest that acne is an inflammatory disease at its core[*].
The types of fat you eat play a key role in your inflammation levels. And when it comes to omega fatty acids, it’s all about your ratios.
Several sources suggest that humans evolved eating a diet with a 1:1 ratio of omega-3 to omega-6. In contrast, the standard American diet has a ratio of around 15:1, with omega-6 fats representing the vast majority[*].
As the Standard American Diet has shifted over the last 100 years, there’s also been a steady rise in obesity and chronic inflammation.
Excessive amounts of omega-6 fatty acids promote a wide range of diseases and are highly inflammatory[*].
But there’s hope yet — if you increase your omega-3s, it may help combat the adverse effects of high omega-6s.
When researchers gave a group of patients with acne fish oil supplements (which are rich in omega-3s), 8 out of 12 subjects reported significant improvement in inflammation and skin lesions[*].
Whether omega-6 fatty acids are causing inflammation or they’re inhibiting the anti-inflammatory effects of omega-3s — it’s still unclear. Either way, focusing on omega-3 rich foods while watching out for omega-6-rich foods may be the key to lowering inflammation[*].
#4 Western Diet
The Western diet is high in processed carbs, omega-6 fatty acids, and low-quality dairy products. It should come as no surprise then, that there is a strong correlation between the Western diet and acne[*].
No one pathway has been identified, but it’s likely that the combination of low-quality dairy, processed carbs, and omega-6 fats activate genes that can trigger the progression of acne[*].
It’s well established that dairy and sugar, two ingredients commonly found in chocolate candy, can trigger IGF-1. But the question of whether chocolate itself causes or exacerbates acne is still up for debate.
In an in vitro study, researchers found that chocolate increased inflammation in cells associated with acne, suggesting that chocolate itself may play a role inflammation and, subsequently, acne[*].
In another study, researchers gave either chocolate or jelly beans to college students and then assessed their acne development 48 hours later. The students that ate chocolate had a statistically significant increase in acne lesion, as compared to the jelly bean group[*].
If you’re struggling with acne, it may be a good idea to add chocolate to your avoid list, at least for a few weeks to see if it makes a difference.
A keto diet doesn’t just lower the glycemic load of your meals — it virtually eliminates it. Processed carbs and sugar are out — as are all grains, high-carb vegetables, and fruit.
The keto diet is known for reducing blood sugar levels and insulin response, which will also eliminate IGF-1-related increases in sebum production.
Ketones — the compounds that your body creates for energy when you run out of stored glucose — are anti-inflammatory. Beta-hydroxybutyrate (BHB), the most abundant ketone your body makes when you’re in ketosis, has anti-inflammatory properties that may decrease systemic inflammation and may help with those breakouts[*].
If you’re currently struggling with acne, or you’re trying to prevent a breakout, first try avoiding these acne-triggering foods:
- Highly processed foods (white bread, white pasta, bagels)
- Sugar (foods that are high in sugar like cookies, ice cream, candy, cake, brownies, pastry)
- Dairy foods (butter, milk, cheese)
- Vegetable oils high in omega-6 fatty acids (sunflower oil, corn oil, soybean oil)
- Fried foods
Salmon and other omega-3-rich foods mackerel, sardines, chia seeds, and hemp seeds may help reduce inflammation[*].
#2 Pumpkin Seeds
#3 Leafy Greens
This golden root may improve the health of your skin through its anti-inflammatory and anti-bacterial properties[*].
#5 Green Tea
In addition to cleaning up your diet, here are some other lifestyle tips that can help keep your skin acne-free.
- Keep a consistent skincare routine by washing your skin in the morning and evening to keep your pores open — especially if you have oily skin
- Avoid picking at pimples
- Don’t overexpose your skin to the sun
- If you have oily hair, keep it out of your face and be sure to shampoo often
- Wash your face after exercise or sweating
- Find ways to manage stress
- Keep your bedsheets, and especially your pillowcases, clean
The Takeaway: Will the Keto Diet Help Acne?
Switching to a low-carb ketogenic diet may help prevent and clear up acne. Hormones like insulin and IGF-1 are implicated in the progression of acne because they increase the oil production of your skin, and may trigger the growth of excess skin cells.
A ketogenic diet keeps these two hormones under control, and therefore could help you avoid the detrimental effects that high levels can have on your skin[*].
The anti-inflammatory effects of the ketogenic diet may also contribute to calming your skin and clearing your complexion[*].