What causes them: Too many games of beach volleyball (or other outdoor exercise). Muscle cramps result from overexertion and dehydration. When you don't have enough fluid in your system, it leads to an electrolyte imbalance that causes your muscles to cramp up. Sodium, calcium, and potassium are the main electrolytes lost through sweating during exercise.
What to eat: Replenish electrolytes with a sports drink that contains them and drink water. Potassium-rich foods include bananas, raisins, potatoes, and spinach.
What causes it: Age-related macular degeneration is the most common cause of vision loss and blindness in people over the age of 55. This occurs when the central part of the retina (macula) becomes damaged.
What to eat: The retina is actually made up of vitamin A, Ely tells WebMD. Thus, foods rich in this vitamin -- along with beta-carotene, zinc, and Vitamins C and E -- are beneficial to the eyes. Good sources are dark green vegetables like kale, chard, and mustard greens, plus bell peppers, carrots, and blueberries. Eat eggs for their high dose of lutein, an important antioxidant that also helps prevent eye damage.
What causes them: Sun exposure can trigger cold sores in people who are prone to them.
What to eat: The amino acid L-lysine has been shown in some small studies to help, but larger studies are needed to confirm these findings. Sandon says a deficiency in B vitamins and riboflavin can make you usceptible to cold sores. She recommends eating fortified cereals and bread or taking a B-complex vitamin.