Summer eating

One of the simple pleasures of a lazy summer day is to be able to enjoy a refreshing slice of watermelon either at the beach, at a picnic, or fresh from the farmer's market. Delicious and nutritious, watermelon is one of those guilt-free indulgences we can all savour: one cup of watermelon packs only about 50 calories! And with recent research suggesting that watermelons may exhibit effects similar to those of Viagra® (sildenafil*), some people may have even more reasons to enjoy the juicy, thirst quencher.

Watermelons are not only cooling treats for when the mercury starts to rise; they are also loaded with healthy nutrients such as vitamin A (including beta-carotene), vitamin C, potassium, lycopene, and magnesium. Vitamins A and C and lycopene are antioxidants, which are substances that work to help negate the harmful effects of substances called free radicals.

Research has suggested that a diet high in fruits and vegetables that have plenty of antioxidants can reduce the risk of heart disease, some cancers, and Alzheimer's disease. A cup of watermelon provides 25% of the recommended daily value of vitamin C and 6% of the recommended daily value of vitamin A. Additionally, researchers have found that lycopene, a nutrient most traditionally associated with tomatoes, is found in equal or greater quantities in watermelon.

Watermelons also provide significant amounts of vitamin B6 and vitamin B1, both of which are necessary for energy production. In combination with the minerals and vitamins already described, these B vitamins add to the high nutrient richness of watermelon. Due to its high water content (watermelon is 92% water by weight) and low calorie count, watermelon is a good choice to satisfy your hunger while you try to eat a healthy diet. Think of them as nature's answer to the heavily marketed "vitamin water" craze.

Need one more reason to finish off a casual summer BBQ with a sweet slice of watermelon? The fruit contains the amino acid called citrulline. A recent study done by researchers at Texas A&M University's Fruit and Vegetable Improvement Center showed that citrulline, which converts into another amino acid called arginine, may boost nitric oxide levels. This effect causes relaxation of the blood vessels similar to the way Viagra®, the popular medication used to treat erectile dysfunction, works. However, researchers also caution that the benefits of watermelon are not as organ-specific as Viagra®.

There are other benefits of citrulline. Citrulline, through its conversion into arginine, benefits the heart, circulatory, and immune systems. Arginine boosts nitric oxide levels, which subsequently relaxes blood vessels and lowers high blood pressure. It also removes ammonia, a harmful toxin, from our body and has been shown to improve insulin sensitivity in people with type 2 diabetes with insulin resistance.

Besides the textured, watery flesh of the fruit, watermelon seeds are also widely eaten as a snack. They are rich in iron and protein and are often pressed for oil or roasted and seasoned.

So if you are planning on dining al fresco this summer, or simply looking for a quick and convenient refreshment to serve to unexpected company or rambunctious children, reach for watermelon. The kids will enjoy its crisp taste and messy juices, the adults will enjoy its refreshing flavours, and everyone will benefit from its nutritious value.


Brennan Robertson, Hon. B.Sc. (Nutrition)

*All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol®). The common name is the medical name for the medication (e.g., acetaminophen). A medication may have many brand names, but only one common name. For information on a given medication, check our Drug Information database. For more information on brand names, speak with your doctor or pharmacist.