4 Foods That Can Cause Oily Skin + What To Eat Instead, From An RD
Some people naturally have more oily skin than others (thanks, genetics!), but you do have the power to influence the amount and composition of oil in your skin. And while introducing the right topicals to your skin care routine is important, you might want to consider approaching your oily skin internally as well—which means it's time to take a look at your diet.
What's the connection between oily skin and diet?
First and foremost: Oily skin is not a problem in and of itself. Everyone needs some oil to protect the outer layer of skin from losing too much water, and your sebum consists of fatty acids, ceramides, sugars, wax esters, and other chemical compounds that provide antioxidants to the skin. It's that overproduction of sebum that can be an issue, clogging pores and ultimately causing acne.
And when there is a noticeable imbalance, like excessively oily skin, it usually means that there is imbalance internally. That's where diet comes in: While foods may not be able to treat acne, per se, they can definitely exacerbate or calm the conflict on the skin.
What foods cause oily skin?
Below, the four main culprits:
Unhealthy vegetable oils.
In a Western diet, the ratio of omega-6 to omega-3 fatty acids in the diet is much higher than in non-Western diets (10 to 20:1 versus 2 to 3:1, to be exact). Omega-6 fatty acids can be involved in pro-inflammatory processes in the body and are associated with the development of inflammatory acne. But that doesn't mean that oils high in omega-6s, like most vegetable oils, are unhealthy. Just that most Americans are getting way too much of this type of fat and not enough omega-3s from foods like fatty fish.
High glycemic foods (sugar!).
Overconsumption of foods with a high glycemic index or a high glycemic load is also a main characteristic of a Western diet and is a key factor in acne development or severity. These measures paint a picture of a food's impact on blood sugar levels. So, a food with a high score would be a refined carbohydrate or sugar, like soda or white pasta, and that would increase blood sugar levels more than, say, spinach.
Blood glucose and insulin could affect the skin in a couple of different ways: First, this spike in blood sugar causes the release of insulin and insulin-like growth factor-1 (IGF-1). Insulin then stimulates the production of androgens (male hormones) that can then lead to higher sebum production in the skin, and then lead to acne. Secondly, high amounts of insulin in the blood before or after a meal may make the skin create more skin cells, making acne that's already present worse.
Dairy has long been chastised for contributing to acne and poor skin, but does the food group deserve this reputation? Let's dig into the research: Similar to high-glycemic foods, the amino acids found in milk can promote the release of insulin and IGF-1, which correlates with acne severity. In addition, a systematic review and meta-analysis of dairy intake and acne in almost 80,000 people ranging from 7 to 30 years of age showed that drinking one glass of milk or more per day was associated with a higher likelihood of having acne compared to no milk intake.
It's important to note that while there are some studies that showcase the link between dairy and acne, much of the evidence is largely anecdotal—and individuals who experience acne may have a mild allergy or intolerance to dairy themselves. So, it doesn't mean that everyone needs to cut out dairy, especially if dairy is already part of your diet and you don't experience severe acne. (In fact, dairy has a host of health benefits, outlined here.) The bottom line? If it works for your body (and skin), there's no reason to avoid it.
Contrary to popular belief, greasy, fatty foods don't exactly influence oil production. But that doesn't mean those foods are off the hook; rather, in this scenario, eating these foods isn't the problem—it's touching your face while eating these foods, or even being in a greasy environment (like, say, a restaurant kitchen) that can clog your pores by actually introducing excess oil to the skin.
What to eat instead.
To balance oil production and calm the skin, here are the four food groups to focus on:
Omega-3 fatty acids
One way to help balance that omega-6 to omega-3 ratio mentioned above is to add more foods with omega-3s to your diet. Fatty fish like salmon are a great source of EPA and DHA, two types of highly bioavailable omega-3s. Studies have even shown that increased intake of omega-3s through eating foods like fish and seafood are associated with lower rates of acne. Omega-3s are known for being anti-inflammatory, and they are involved in pathways (such as quelling pro-inflammatory cytokine secretion and leukotriene B4 synthesis) that are beneficial in acne management.
Gamma linolenic acid (GLA)
This is the one omega-6 fatty acid that could specifically promote skin health. This fat is primarily found in the seeds of evening primrose, often found in supplements, borage oil, and hemp hearts. Topical and dietary supplementation of GLA oils has been studied for inflammatory skin conditions, and one intervention study in healthy women found that both intake of GLA-rich borage oil and flaxseed oil (rich in the omega-3 alpha-linolenic acid) experienced benefits to skin health including decreased reddening and improved hydration after 12 weeks. And, as you may know, hydration is crucial when it comes to oil production—in fact, dehydrated skin may overproduce oil to compensate for a lack of moisture.
Probiotics are a great addition to a skin-healthy diet, namely due to the gut-skin axis. The gut microbiota (aka, the little live critters like bacteria) can affect acne by producing beneficial substances that regulate new cell generation, fat metabolism, and other metabolic functions that influence skin health. Try fermented foods like yogurt, kefir, and kimchi, which often contain live cultures or probiotics, or one of the other probiotic-rich favorites here.
Prebiotics act as fuel for the good bacteria residing in the gut. Prebiotics like asparagus, bananas, Jerusalem artichoke, and chicory root are fermented by those good bacteria and produce beneficial substances like short-chain fatty acids for the body to use. Since gut health is tied to skin health (and just health in general, while we're at it), it's important to include both pre- and probiotics in the diet. (Peek a full list of prebiotic-rich foods here.)
Oily skin and acne could use more than just a topical solution; take a step back and look at the bigger picture like diet and gut health. Some foods may trigger or exacerbate already oily and acne-prone skin, and some foods may quell inflammation associated with skin conditions.
While research on the connection between food and skin is still evolving, the current evidence shows that it's not individual foods that will grease up your skin—it's overall diet quality. That said, to keep oily skin at bay, make sure to get your fill of healthy fats, complex carbs, and good bacteria.
Molly Knudsen, M.S., RDN is a Registered Dietician Nutritionist with a bachelor’s degree in nutrition from Texas Christian University and a master’s in nutrition interventions, communication, and behavior change from Tufts University. She lives in Newport Beach, California, and enjoys connecting people to the food they eat and how it influences health and wellbeing.