Acne and Carbs: Insulin Resistance Links Obesity and Acne, Study Shows

But Neither Acne Nor Obesity Is Caused By Eating Any Particular Food

For generations mothers, grandmothers, and nutrition experts have been telling teens who have acne to avoid chocolate, fried foods, and nuts—and teens keep getting acne anyway. Scientists have never been able to prove that any particular food always causes acne, but that could be because until recently scientists were not looking at the problem in the right way.

Sugar Does Not Cause Acne, If You Just Eat a Little

Scientists disproved the "candy bar theory" of the origins of acne beginning back in 1967 when Drs. Jill Morland, John Yudkin, and D. G. G. Bett showed that people who had acne don't eat any more sugar than people who do not. Sugar is not a toxin that can make your skin break out. But candy bars and similar sugary treats are not necessarily good for people who have acne, either.

A more modern understanding of the interrelationship between sugar and acne involves the concept of "glycemic load," the total amount of digestible carbohydrate people consume in their daily diets. The glycemic load consists of all the foods that the body readily converts into glucose. This includes sugar and candy, of course, but also bread, chips, potatoes, rice, and every kind of dessert.

READ Natural and Home Remedies for Acne (Pimples)

The glycemic load is a measurement not just of which foods a person eats, but how much of those foods a person eats. Someone who never eats candy bars but who loads up on bread and potatoes might have a higher glycemic load than someone who eats three or four or five chocolate bars every day of the week.
 

Glycemic Load and Acne in Women

The reason glycemic load makes a difference in the health of the skin in women is that all the extra glucose released into the bloodstream by the digestion of food has to go somewhere—and the place it goes is the ovaries.

The burning of sugar inside a cell releases free radicals that can damage DNA. Most of the cells in the body can protect themselves against a flood of sugar from the bloodstream by becoming insulin resistant. They switch off receptor sites that would be activated by insulin and bring sugar inside the cells.

The ovaries, however, do not have this protective mechanism. When some women overeat starchy and sugary foods, they ovaries absorb extra sugar and go into overdrive producing both estrogen and testosterone. Some of the testosterone circulates to the skin, where it can increase production of sebum, which clogs pores. (It can also trigger hair growth.)

Acne is not inevitable when the pores make more oil. It's just a lot more likely, if appropriate cleansing and skin treatment methods are not followed.

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Glycemic Load and Acne in Men

Glycemic load has a different effect on the skin in men. In men, consuming a lot of carbohydrate forces the pancreas to release a lot of insulin. The additional insulin interferes with the action of a substance known as sex hormone binding globulin. More testosterone circulates unbound and ready to be converted into a form that stimulates the production of sebum in the skin.

As with women, excess oil production in the skin of men does not immediately lead to acne. The pores that produce excess oil are usually actually clogged by clumps of dead skin cells, and stress on the skin, not acne bacteria, is what causes blackheads and whiteheads to morph into pimples. In both males and females, however, eating less carbohydrate in general reduces acne.

How to Use a Low-Carb Diet to Fight Acne

When it comes to causing acne, some kinds of sugar are worse than others. Sugary soft drinks laced with caffeine are among the very worst additions to your diet if you have acne-prone skin. The combination of sugar and caffeine stimulates the production of a substance known as Substance P.

This compound transmits pain messages to your skin. Your skin responds by releasing a substance known as corticotrophin stimulating hormone, which in turns causes a specialized structure known as a mast cell to burst. Mast cells release histamine which makes your skin turn red—just 10 or 15 minutes after you drink Coca Cola, Dr. Pepper, Red Bull, or any other beverage that contains both sugar and caffeine.

Even if you never indulge in sugar-sweetened soft drinks and you don't eat candy or desserts, you can still have problems due to excess carbohydrate consumption. Conversely, getting fewer calories from carbohydrates and more calories from protein helps clear up your skin.
 
Doctors recruited volunteers who had acne to eat a relatively high-protein diet for two weeks. This diet provided 44% of calories from protein, 35% of calories from carbohydrate, and 21% of calories from fat. In just two weeks, free testosterone levels began to fall and the volunteers began to notice clearer skin.

Then the research team asked the volunteers to eat a relatively high-carbohydrate diet. This diet provided 10% of calories from protein, 70% of calories from carbohydrate, and 20% of calories from fat. In just two weeks, testosterone levels began to rise and the volunteers began to notice new blemishes.

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Most people find that when they eat high-protein foods, they do not crave high-carb foods. The body also can convert excess amino acids digested from meat and other high-protein foods into glucose, so it is not a good idea to overindulge even on a healthy diet. But when total calories are kept to the levels the body needs for daily energy, high-carb diets help to resolve acne.

There are also certain foods that have a measurable effect on acne, and they probably are not the foods you would expect.

Dutch scientists recruited 302 people who had acne for measurements of skin oiliness with a device called a sebum meter. They then drew blood to check nutrient levels and asked the volunteers for food diaries listing their food choices. The findings?

• Margarine and cooking oil made acne worse, but dairy fat (in whole milk, ice cream, butter, and yogurt), eggs, fish, and meat did not. Even lard did not have a negative effect on acne.
• Foods that are high in lycopene, such as tomatoes, passionfruit, and watermelons, increased oiliness of the skin.
• Excessive consumption of carrots tended to dry out the skin. When the skin loses moisture, it is more easily irritated, making it pimple-prone.

And the Dutch researchers learned that one popular nutritional supplement also increased acne problems. The skin of volunteers who took supplemental vitamin E (in the form of alpha-tocopherol) produced 30 times as much sebum as the skin of volunteers who did not.

Your mother may be right about pizza causing acne—but it's the tomato sauce, not the cheese. And you may also need to avoid milk chocolate—because of the sugar, not the chocolate. But if you avoid excessive calorie consumption and make a point of eating protein at every meal, you may be able to avoid the insulin resistance and related hormonal problems that make acne-prone skin break out.