July 22, 2013

Research shows certain foods can whiten teeth, fight wrinkles and give skin a radiant glow. Here are 6 beauty foods that do double duty to benefit your health too!

Want to know what to eat for better health? Yes, please. What about what to eat to keep yourself looking fabulous? Of course! Put the two together and you get: 6 foods that have beauty- and health-boosting benefits. A two-for-one! Here are 6 double-duty beauty foods to add to your diet.

-Brierley Wright, M.S., R.D.

1. Strawberries

Beauty benefit: Keep teeth healthy
Strawberries are the third-best food source of polyphenols (behind only coffee and olives), according to a 2009 Journal of Dentistry review. That's good news, since researchers believe these compounds inhibit the breakdown of starches in the mouth (thus limiting the resulting sticky sugars that adhere to teeth as plaque) and also fight the bacteria that contribute to tooth decay and gum disease. Scrubbing your teeth with strawberries will whiten them, but because the berries are so acidic, dentists warn that using this home remedy frequently could damage the enamel.

Health benefit: Protect your heart
A Harvard study published in January links eating berries to a lower risk of heart attacks among younger women. The study followed women 25 to 42 who ate more than 3 (1/2-cup) servings of strawberries and/or blueberries each week over an 18-year span. The findings? These women had a 34 percent reduced risk of heart attack compared to those who ate less than one serving per week. Researchers point to the berries' anthocyanin content as the protective factor. Tip for picking: The reddest berries have the most anthocyanins. (Find more surprising health benefits of strawberries here.)

2. Carrots

Beauty benefit: Give your skin a radiant, sun-kissed glow
Eating more carotenoids-orange and yellow pigments found in carrots and other foods, including red and yellow peppers, spinach and other dark leafy greens-can create an au naturel tan, suggests a study published in the journal Evolution and Human Behavior. "Carotenoids are thought to be stored in the fat under the skin, and are also secreted through the pores, where they are then absorbed back into the top layer of the skin, giving it a golden color," explains study author Ian Stephen, Ph.D., now at the University of Nottingham. If you already eat five portions of fruits and vegetables, though, adding another five (or loading up on only carrots) won't necessarily give you a more radiant flush. It may, in fact, make you too yellow or orange, warns Stephen.

Health benefit: Improve your memory
Carrots also contain luteolin, a flavonoid believed to reduce inflammation that can lead to cognitive decline. In a 2010 The Journal of Nutrition study, mice that ate a diet that included luteolin had better spatial memory (e.g., how quickly they found a platform in a water maze) and less inflammation than mice that didn't get any luteolin. Luteolin is found in bell peppers, celery, rosemary and thyme.

3. Green Tea

Beauty benefit: Fights bad breath
For tea-rific breath, try a cup of tea. Studies suggest that drinking unsweetened black or green tea may help ward off bad breath. Both types of tea contain antioxidants called polyphenols that can help destroy the growth of bacteria that cause bad breath-although green tea contains more because it is processed in a different way. A study conducted at Pace University, for example, found that green tea extracts were effective at fighting several types of oral bacteria by preventing their growth. Polyphenols also reduce those nasty sulfur compounds. (Find more foods to get rid of bad breath here.)

Health benefit: Tamps down inflammation
Green tea is full of potent antioxidants that help quell inflammation. (Chronic inflammation plays a significant role-as either a cause or effect-in many diseases, including type 2 diabetes, autoimmune diseases and the three top killers in the United States: heart disease, cancer and stroke.) In fact, researchers from Texas Tech University Health Sciences Center in Lubbock recently found that green tea can inhibit oxidative stress and the potential inflammation that may result from it. "After 24 weeks, people who consumed 500 mg of green tea polyphenols daily-that's about 4 to 6 cups of tea-halved their oxidative stress levels," says Leslie Shen, Ph.D., the study's lead author. (The placebo group didn't see a single change.)

4. Coffee

Beauty benefit: Protects against skin cancer
Drinking a single cup of coffee daily may lower your risk of developing skin cancer. In one study of more than 93,000 women, published in the European Journal of Cancer Prevention, those who drank 1 cup of caffeinated coffee a day reduced their risk of developing nonmelanoma skin cancer by about 10 percent. And the more they drank-up to about 6 cups or so per day-the lower their risk. Decaf didn't seem to offer the same protection.

Health benefit: Brain gains
Moderate coffee drinking-between 1 and 5 cups daily-may help reduce risk of dementia and Alzheimer's disease, as well as Parkinson's disease, studies suggest. How? Coffee's antioxidants may prevent some damage to brain cells and boost the effects of neurotransmitters involved in cognitive function, say experts. Preliminary studies have noted that as coffee (or tea) intake rises, incidence of glioma, a form of brain cancer, tends to drop. Some researchers speculate that compounds in the brews could activate a DNA-repairing protein in cells-possibly preventing the DNA damage that can lead to cells becoming cancerous. (Read about more health benefits of coffee, plus cons to consider here.)

Must-Have: Easy Coffee Recipes

5. Tofu

Beauty benefit: Keeps wrinkles at bay
Tofu-and other soyfoods, such as edamame and soymilk-may help to preserve skin-firming collagen because it is rich in isoflavones. In a study published in the Journal of the American College of Nutrition, mice fed isoflavones and exposed to ultraviolet radiation had fewer wrinkles and smoother skin than mice that were exposed to UV light but didn't get isoflavones. The researchers believe that isoflavones help prevent collagen breakdown.

Health benefit: Improves cholesterol
Eating 25 grams of soy protein daily (about 1 1/4 cups of tofu or edamame) may help lower your "bad" LDL and total cholesterol levels, suggests a review of 30 studies. One hypothesis is that soy protein lowers cholesterol by helping the liver clear more LDL from the body.

6. Salmon

Beauty benefit: Protects your eyes
A recent analysis of nine studies that included more than 88,000 participants suggested that people who ate at least two servings of fatty fish (such as salmon, sardines, mackerel, herring or trout) per week were about one-third less likely to develop advanced age-related macular degeneration (AMD) than those who didn't. Lead scientist Elaine Chong, Ph.D., a research fellow at the Centre for Eye Research at the University of Melbourne, Australia, explains that omega-3 fatty acids-particularly DHA-in fish are key components of the nerve cells in the retina. "DHA is found in much higher concentrations in the retina than in other parts of the body," she notes, "thus, a deficiency may trigger AMD." So commit to eating more fatty fish, and don't stop there: shellfish, such as oysters and crab, provide good amounts of zinc, another nutrient that's found in the retina and may also help protect against AMD.

Health benefit: Mood booster
Those omega-3s in salmon (and other oily, fatty fish) alter brain chemicals linked with mood-specifically dopamine and serotonin. Low levels of serotonin are linked with depression, aggression and suicidal tendencies, while dopamine is a "reward" chemical that the brain releases in response to pleasurable experiences, such as eating or having sex.