A member of the citrus family, kumquats look and taste very similar to oranges but are smaller and more oval-shaped. "They contain all of the same nutritional and skin benefits of oranges with an abundance of vitamin C, beta-carotene, B vitamins, flavonoids and minerals," says Poon. "With an edible peel that is especially rich in antioxidants and fiber, kumquats are great for collagen synthesis and wound healing, as well as digestive and immune health." She recommends snacking on kumquats daily to score an added dose of antiviral and antibacterial protection, which will certainly come in handy as flu season arrives.

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Walnuts are an excellent source of omega-3-fatty acids, which are also found in fish. So, if you're not big into fish, you'll definitely want to pile walnuts into your salads or grab a handful on the go to help add shine back into your hair. "Walnuts also contribute to a younger and smoother skin complexion and may help to make you look younger in the process," says Martinez.

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For that desirable dewy glow as fall temperatures plummet, be sure to have your fair share of sweet potatoes, which are full of beta-carotene, vitamin D and anthocyanins. "These nutrients work hard in our body to neutralize oxidative stress and age-related damage to our cells," explains Poon. "Sweet potatoes are also great for keeping the skin hydrated because they are rich in potassium and pantothenic acid." In addition to eating sweet potatoes, she recommends applying mashed sweet potato topically as a mask for immediately moisturizing effects.

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Sweet and savory tasting at the same time, butternut squash isn't only a delicious fall ingredient, it's also great for your skin. "Butternut squash contains a lot of vitamin C, which studies have linked to healthy skin," says Williams. "That's why you see vitamin C in a lot of beauty products, like serums." She recommends enjoying butternut squash as often as you can when it's in season (during the fall). "Typically 1/2 cup is a good serving size for women," she adds.

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Another nutrient-packed seed that's generally harvested in October is sunflower seed, which provides a great source of vitamin E to help moisturize and soften skin. "Acting as an antioxidant, vitamin E also helps eliminate free radicals that cause damage to skin," adds Bente. She recommends a hearty serving of 1/2 cup sunflower seeds, in their shells, which is only about 130 calories and provides more than 35 percent of your daily vitamin E requirements.

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