Do foods with a low glycemic index improve skin?

Legumes and whole grains.
© iStockphoto.com/luca manieri
The foods you eat affect the health of your skin.

Eating foods with a low glycemic index has become a popular diet trend. What you eat can affect the health of your skin, so you may wonder if eating a low-glycemic-index diet will contribute to a blemish-free face and a healthy glow. To understand how the low glycemic index may affect you and your complexion, you must first understand what the index is and how it works.

The glycemic index measures how rapidly different foods make your blood sugar rise. For example, sugary foods, such as candy and soda, rank high on the glycemic index -- they make your blood sugar rise quickly. That blood sugar level won't stay high for long, though -- you'll experience a "crash" feeling when it drops again. In contrast, low-glycemic foods raise your blood sugar slowly, helping to keep your blood sugar more stable so you won't get that crash. People on a low glycemic index diet eat foods that have lower glycemic scores, typically below 55 [sources: Boyles, Mayo Clinic].

Low-glycemic foods include high-fiber foods, such as whole grains, that take more time for your body to break down. Processed foods are usually high-glycemic foods that your body burns up rapidly. However, some healthy foods rank high on the glycemic index -- even though they're not processed -- and some sodas and junk food register low on the glycemic index. For example, a Snickers bar has a glycemic index score of about 55 [source: Boyles]. Obviously, eating junk food isn't good for your health, so making diet decisions based on glycemic scores may not be the best idea [source: Magee].

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To complicate matters further, research indicates that the glycemic index of a food varies for different people -- it can even vary for one person at different times of day, Also, a food's index score can change depending on factors like its ripeness, the cooking method and the foods its eaten with [source: Boyles].

Using the glycemic index as a guide for your diet or for your skin's health can be challenging. Some foods that rank high on the glycemic index contain important nutrients that benefit your skin, and some low-ranking foods provide no benefit to your skin. Keep reading to learn more about the glycemic index and how it affects your skin.

Glycemic Index and Skin Health

Maintaining a Balanced Diet
If you're going to restrict what you eat, make sure you balance your diet by eating healthy food that gives you nutritional benefits similar to the foods that you eliminate. The trick to managing a low-glycemic-index diet while maintaining healthy skin is moderation and a focus on good nutrition. For more information, visit MyPyramid.gov [sources: USDA, WebMD].

You may have heard that a certain diet caused your friend's skin to break out or become dry and scaly. While the low-glycemic index diet doesn't typically have the same extreme effect on your skin as some other diets, it does have its own pros and cons.

On the positive side, new research shows that a low-glycemic-index diet may help prevent or alleviate acne. First, you should know that contrary to popular myth, eating certain foods, such as chocolate or greasy pizza, won't make you break out. However, recent research suggests that modifying your overall diet to eat more low-glycemic-index carbohydrates can result in fewer zits. While this study has generated a lot of interest, further research is being conducted to verify these results [sources: American Academy of Dermatology, Science Daily].

On the negative side, the low-glycemic-index diet restricts foods that can benefit your skin. For example, oranges are high on the glycemic index, but they contain vitamin C, which is an antioxidant and a collagen booster. Antioxidants repair damaged skin and protect skin from free radicals that can cause wrinkles, and collagen is an essential protein that helps keep skin tissue strong and firm [sources: Magee, Real Age].

Although maintaining a healthy diet promotes a healthier complexion, relying on a low-glycemic-index diet to do this probably isn't the best solution. Following a low-glycemic-index diet may reduce acne, but eating too many of these foods and avoiding certain foods, such as fruit, could cause other skin problems by depriving your skin of important nutrients.

If you want to try a low-glycemic-index diet, read on to learn how to use a glycemic-index chart.

Glycemic Index Table

Carbohydrates and Breast Cancer
A recent study compared women with high-glycemic-index diets to women with low-glycemic-index diets over a period of 17 years. Women whose diets had the highest glycemic index had a 44 percent increased risk of developing certain types of breast cancer. Researchers speculate that the increased concentrations of insulin and sex hormones caused by a high-glycemic-index diet may encourage breast cancer cells to grow [source: Reuters Health].

If you want to try a low-glycemic-index diet, you need to know what foods to eat and which ones to avoid. A glycemic index table can help you determine high- and low-glycemic foods, but reading a table can be confusing. A glycemic index table may rank some healthy foods the same as it ranks some junk food. For example, a carrot and a pound cake may have similar scores on a glycemic index table -- only their glycemic index is ranked, not their overall health value.

To help alleviate this confusion, researchers have created the glycemic load, which takes a food's carbohydrates into account. The amount of carbohydrates affects how fast and how high your blood glucose level rises after you eat. To calculate the glycemic load, you multiply the glycemic index of a food by the number of carbohydrates per grams found in a single serving of that food. Then you divide the total by 100 [source: Higdon].

The table below provides some examples of the glycemic index versus the glycemic load of certain foods.

Food Item

Description/Serving Size

Glycemic Index

Carbohydrates/ Grams/Serving

Glycemic Load

Apple juice

pure, clear, unsweetened

8.5 fluid ounces/250 ml

63

30

13

Bagel

frozen, white

70 grams

103 +/- 5

35

25

Whole grain bread

30 grams

89

14

9

Cornflakes

30 grams

130

26

24

Fruit Loops

30 grams

98 +/- 13

26

18

Apple

120 grams

57

16

6

Banana

ripe

120 grams

51

25

13

Peas

frozen, boiled

80 grams

55

7

3

Sweet corn

boiled

80 grams

86

18

11

[source: Foster-Powell]

To prevent your low-glycemic-index diet from negatively impacting your skin, you need to maintain a nutritional balance. This means you need to consider both the glycemic load and the glycemic index level of the foods you eat, and you need to make sure you're getting the necessary vitamins and minerals in your diet as well. To get the most from a low-glycemic-index diet, consult a doctor, dietician or nutritionist.

For more information on the glycemic index, see the links on the following page.

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Sources

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