Unhappy woman squeezing out pimple, in pain

Adult acne is on the rise, with more adults dealing with acne now than ever before. It is estimated that around 40% to 55% of the adult population aged between 20 and 40 are suffering from persistent acne.

While there are quite a few treatment options for acne out there, prevention is always better than cure. 

How do you prevent adult acne? 

There are several steps that you can take, one of which involves making changes to your diet. There are a number of foods out there that have been identified as common acne triggers, making these seven foods ones that you should try to cut out of your diet as much as possible. 

Dairy Products

There are numerous studies that have now been carried out on the link between acne and dairy, proving that there is quite a strong correlation between the two. One major study concluded that consuming dairy products as an adult is the biggest cause of acne out there. This is because around 65% of adults are actually lactose intolerant after they have passed the infancy stage.

Assorted dairy products

How does dairy cause acne? 

There isn’t a specific answer to this yet. However, there are a few theories to this: 

  • Dairy increases the body’s insulin levels, which has been shown to exacerbate acne 
  • Dairy contains specific amino acids that trigger the liver into producing more IGF-1. This is a growth factor that has quite a strong effect of the development of acne 
  • Dairy increases the activity of mTORC1 in the body, which is an enzyme that significantly contributes to acne breakouts 
  • Dairy itself often contains growth hormones that were given to the cow (or whichever other animal your dairy has come from). This can interfere with your own hormones, leading to an increase in oil production and a greater chance of breakouts 

Fortunately, cutting dairy out of your diet is now so much easier than ever. There are numerous dairy alternatives out there that you can opt for instead, whether this may be in the form of milk, cheese, yogurt, or anything else. R

Refined Sugars and Grains

Another common dietary trigger of adult acne is refined grains and sugars. 

Some examples of these include: 

  • White bread 
  • White pasta 
  • White rice and white noodles 
  • Sugar-filled drinks 
  • Sweeteners, such as honey, maple syrup and agave

Why are these foods so bad?

The main reason is because they are absorbed extremely quickly into the bloodstream. This then causes a quick spike in your blood sugar levels.

How does that connect to acne? 

Because when your blood sugar levels rise, so do your insulin levels. This is so that all of those extra blood sugars can be taken out of the bloodstream and delivered to your cells. 

Unfortunately, high insulin levels are not good for those who are susceptible to acne (or for anyone, for that matter). 


Because insulin causes your androgen hormones to become much more active. It also increases the amount of IGF-1 (a growth factor) in your body. 

All of this has the result of increasing the amount of oil that your skin produces, while also causing your skin cells to grow much faster than they should. The excess oil on your skin, plus the build-up of dead skin cells, combine together to trigger a breakout. 

Has this been proven? 

Yes, by quite a few different studies. They showed that those who eat more refined carbs tend to experience a much greater rate of acne than those who do not.

Do refined carbohydrates and sugars feature quite heavily in your diet? 

If so, it may take you a while to make the necessary changes, but there are plenty of alternatives out there. 

Here are a few tasty whole grains to try: 

  • Barley 
  • Oats 
  • Quinoa 
  • Farro 
  • Millet 

Fast Food

There is quite a strong connection between fast food and acne. 

In fact, one study discovered that those who regularly consume fast food items have a 24% increased chance of developing acne, compared to those who do not consume much fast food. 

How does fast food cause acne? 

Just like with dairy, there isn’t yet an exact answer to this. 

One of the reasons could be due to the amount of refined carbohydrates and sugars that can be found in fast food. As you know from above, refined sugars and carbs are a big adult acne trigger. 

Woman eating burger

Fast food is also regularly cooked with refined oils, and often contains dairy, salt and animal products, none of which will be doing your acne any favors. 

Don’t get it wrong – treating yourself to an easy fast food meal once in a while isn’t going to cause any serious problems. The issue arises when fast food is consumed as a regular part of the diet.

Whey Protein

Do you consume whey protein? 

This food is becoming increasingly popular, with more and more people turning to protein powder to help them build up their muscles. 

As mentioned above, dairy is a huge acne trigger, and whey is a dairy product. 

It increases the activity of IGF-1, and while this hormone does stimulate muscle growth, it also increases the amount of oil that your skin produces.

Studies have found that even those who have never dealt with adult acne in the past often find themselves left with breakouts after consuming whey protein. 

A scoop of green whey protein

Don’t want to give up your protein shakes? 

You don’t have to, as there are plenty of protein powder alternatives out there that don’t contain whey. 

Here are a few to try: 

  • Pea protein powder 
  • Hemp protein powder 
  • Brown rice protein powder 

Both pea and hemp protein powders contain all of the necessary amino acids for building muscle. Brown rice contains less, which is why it should be used in conjunction with another plant-based protein powder. 

Foods High in Omega-6 Fatty Acids

Essential fatty acids are fatty acids that the body does not produce itself, meaning that you need to obtain these through your diet. 

There are a variety of these essential fatty acids out there, with two of the most important ones being omega-3 fatty acids and omega-6 fatty acids. Both of these are key when it comes to healthy skin. 

You’re probably thinking…

If omega-6 fatty acids are so good, how come they can cause acne? 

Omega-6 fatty acids are only good when you consume them in the right ratio with omega-3 fatty acids. 

The ratio of omega-6 to omega-3 should be 4:1. If you are trying to counter the visible signs of aging in your skin, dermatologists may even recommend a ratio of 1:1. 

Wondering what your current ratio is? 

Well, if you’re consuming an average American diet, your current ratio is probably somewhere between 12:1 and 25:1.

As you can see, this is way off from the ideal…

Why is the average diet so off balance when it comes to the omega-6 and omega-3 ratio? 

Because the main foods consumed are extremely high in omega-6 fatty acids, but low in omega-3s. 

Processed seed and vegetable oils are the main culprit, and these include: 

  • Sunflower oil 
  • Corn oil 
  • Soybean oil 
  • Cottonseed oil 

So, what actually happens when you consume too much omega-6 fatty acids? 

It sends your body into an inflammatory state. 

If you already regularly suffer from acne, then you likely know that inflammation is a huge trigger behind this. It is important to keep inflammation in your body, and skin, as low as possible. 

The fact that the average modern day diet contains so many inflammatory omega-6 fatty acids can have a huge effect on acne. 

What should you do about this? 

For starters, cut the above oils out of your diet. 

Replace these with oils that contain a healthy balance of omega-3s and omega-6s, such as: 

If you are not able to make these changes, you may want to consider an omega-3 fatty acid supplement. This can help to counter the inflammatory effect of all of the omega-6s, therefore reducing the severity of acne breakouts. 

Spicy Foods

Have you noticed that your acne tends to get worse after you have eaten a spicy meal? 

This is more common than you would imagine…

While the spices in your food, such as the hot pepper themselves, don’t actually trigger acne, it is the reaction that your body has in response to this spice that is the problem. 

What happens when you eat overly spicy foods? 

Your body temperature rises, which causes inflammation in the body. Your higher body temperature will also lead to sweating, which, again, can lead to breakouts. 


Because sweating stimulates your skin into producing more oil, which soon clogs up the pores and results in a breakout.

Don’t worry, you don’t have to give up spicy foods…

Since it is the act of sweating rather than the food itself that leads to acne, cleansing your face after you have started sweating will go a long way in preventing spicy food-induced breakouts. 

You could also try to minimize how much you sweat after eating spicy foods. 


By building up your tolerance to spice. Do this by starting with peppers that are low on the Scoville scale, which is the scale that measures how spicy a certain ingredient is. Poblano and Anaheim peppers are good ones to begin with. You can then start working your way up the scale to the medium-heat peppers, such as the popular jalapeno. 

Scoville scale infographic

By allowing your body to slowly get used to the spice, you will reduce the inflammatory reaction that your body has when you do eat a spicy meal. 


Just like with spicy foods, alcohol itself doesn’t cause acne. However, it is the response that your body has to the alcohol that can trigger a breakout. 

When alcohol is consumed, it has a number of different effects on your body that could result in acne: 

  • Weakens the immune system, leaving your body much more susceptible to attacks from acne-causing bacteria 
  • Interferes with natural hormone levels, which then stimulates the oil glands into producing more oil 
  • Causes inflammation 
  • Dehydrates the body. Your skin responds to this by producing more sebum to try to keep itself moist, which only has the effect of clogging up the pores and triggering a breakout 
  • Prevents the liver from properly detoxifying. Excess toxins in the body can cause acne

The type of alcohol you drink also has an effect on this…

Dark liquors increase inflammation, blood sugar levels and dehydration much more than clear liquors. 

When it comes to wine, red wine contains a high amount of tannins. This has the effect of dilating the blood vessels, leading to skin inflammation. 

Don’t want to completely give up alcohol? 

You don’t have to. Just like everything else on this list, moderation is key. 

What counts as moderation? 

Ideally, for women, you wouldn’t drink more than one alcoholic drink a day. For men, this is slightly more, at two drinks per day. Again, the type of alcohol you are drinking makes a difference to how much you can consume. One drink of wine would count as a five ounce measure, whereas if you are choosing liquor for your daily drink, this should only be an amount of around 1.5 ounces. 

While there are plenty of ways in which you can treat adult acne, it is always so much better if you don’t have to deal with the breakout at all in the first place. There are quite a few lifestyle changes that you could make to help reduce the frequency and severity of your acne breakouts, but one of the most important is your diet. By cutting out the seven foods listed above, you will likely notice quite an improvement in your acne in no time at all.