No picnic or backyard party is complete without a watermelon or two. Watermelons are so popular in fact, they are actually one of the most-consumed melons in the entire US, according to statistics.
While we usually associate watermelons with fruit, they are actually both a fruit and a vegetable and are related to cucumbers, pumpkins, and squash. No wonder this melon contains so many nutrients (1)!
These fruit/vegetables are nearly devoid of any calories, being 91 percent water, which makes them a dieter’s best friend. But these refreshing treats are not just a July 4th staple, they also pack a serious punch when it comes to vitamins and nutrients. Just one cup of watermelon gives you 21 percent of your entire vitamin C intake and 18 percent of your vitamin A requirements, according to the USDA (2).
Although we don’t typically do so, you can actually eat the rind of a watermelon, which some say is another reason why they are considered a vegetable. A recent study compared the nutrient content of the flesh and other various parts of a watermelon and they determined there are some pretty impressive concentrations of phenolic antioxidants, flavonoids, lycopene, citrulline, and vitamin C in every part of the watermelon (3, 4).
In short they are much more than a favorite summer food!
Watermelon Health Benefits
You’ve probably never heard of these before.
1. Improves Erectile Dysfunction (ED)
One new study determined that eating watermelon, especially the rind, may hold the key to erectile dysfunction!
Citrulline, an amino acid that is found in all parts of a watermelon, is found in greater proportions in the rind in many cases. This powerful amino acid is associated with numerous health benefits and it can even help to relax blood vessels, much like Viagra, according to one study. Other studies also show that citrulline increases blood flow, a key factor in erectile dysfunction (5).
When eaten, citrulline is further converted to arginine through specific enzyme actions. Arginine, as other studies show, is an amino acid that is highly beneficial for your heart and circulatory system as well as your immune system. Researchers also conclude that arginine can help the urea cycle by removing ammonia and other toxic compounds from your body (6). In total, researchers found that arginine can be helpful in over 100 health conditions (7).
2. Reduces Muscle Soreness
While many studies show that the nutrients and minerals in watermelons can help to soothes sore muscles, one study in particular found that men who drank natural, unpasteurized watermelon juice prior to their workouts, had reduced muscle soreness 24 hours later compared to those who drank a placebo (8, 9).
Another study showed that just one dose of citrulline or watermelon juice as a pre-exercise supplement can be enough to improve your exercise performance, although higher doses are still safe (10).
3. Weight Loss
While you might think weight loss is a given based on the fact that there are only 46 calories in one cup of this delicious fruit, another reason watermelon is so helpful for losing weight is strictly chemical based.
According to a study, the citrulline content in watermelon may be the key to how we store fat. The study showed that a high intake of this amino acid, followed by its conversion into arginine, actually results in the formation of arginine-related molecules called polyarginine peptides. These polyarginine peptides are able to block the “activity of an enzyme called tissue-nonspecific alkaline phosphatase, or TNAP.” Apparently, according to the study, “…when TNAP activity is shut down, your fat cells (adipocytes) tend to create less fat (adipogenesis).”
Based on this, researchers believe that “…the connection between citrulline in food, arginine production by nitric oxide synthase, and fat cell metabolism, may eventually provide additional tools for helping prevent over-accumulation of body fat.” While more research is needed, this is definitely promising news (11).
4. Powerful Anti-inflammatory
What has scientists so interested in the health benefits of watermelons is the fact that they have more lycopene than raw tomatoes. In reality, just 1 cup of watermelon actually has 1.5 times the lycopene content of 1 large tomato.
So, why is this so exciting? Well, lycopene is a key antioxidant. In fact, it is actually considered one of the super antioxidants that can inhibit a number of inflammatory processes, including “the production of pro-inflammatory messaging molecules, the expression of enzymes like cyclo-oxygenase and lipoxygenase that can lead to increased inflammatory response, and the activity of molecular signaling agents like nuclear factor kappa B (NFkB).” (12).
5. Lowers Blood Pressure
What does this mean for you? In layman terms, it means that lycopene can help prevent a whole host of health issues including various cancers (prostate, lung, stomach, pancreas, colon and rectum, as well as esophagus, oral cavity, breast, and cervix) and cardiovascular disease (13,14). It can also help lower cholesterol and blood pressure (15).
The lycopene content in watermelons increases as they ripen, so always eat melons that are a deep red and fully ripe. While there are varieties of yellow watermelons that still contain the amazing health benefits of red watermelons, the darker red melons do contain the highest amounts of lycopene.
Watermelon also contains significant amounts of beta-carotene, another powerful antioxidant typically found in foods like carrots and squash. One study shows that red watermelon contains over 467 mcg of beta-carotene and 6,979 micrograms of lycopene per cup of melon. Like lycopene, the beta-carotene content increases as the watermelon ripens.
6. Improves Eye Sight
By the mere fact that watermelons contain high levels of beta-carotene, you know they are good for your eyes.
Beta carotene is converted in your body into vitamin A, which is extremely helpful for eye health. This powerful antioxidant helps to protect the surface of your eye as well as the mucous membranes from bacteria and viruses by building a protective barrier. It also protects your eyes from age-related macular degeneration and night blindness (16).
7. Raises Your pH Levels
There is an endless array of studies that prove how acidity in your body can destroy your health, wreaking havoc on every organ, tissue and cell thus leading to disease. In fact, in 1931, Otto Warburg, a German scientist, won the Nobel Prize for his work on oxidation, which showed that diseases (specifically, cancer) cannot survive in an alkaline environment (17).
8. Rehydrates Your Body
Watermelon isn’t just mostly made up of water, it also contains electrolytes such as calcium, magnesium, potassium, and phosphate (18). This makes watermelon one of the best foods you can eat to rehydrate your body naturally.
9. Improves Blood Sugar Levels
Watermelon juice is a good source of L-citrulline, which can increase the essential amino acid arginine in the body.
In laboratory trials, an increase in arginine helped keep blood sugar levels balanced, while also lowering cardiovascular risks in obese animals with type-II diabetes (19).
10. Protects Against Cancer
Researchers have found that foods high in lycopene, vitamin C, and other antioxidants have a protective effect against many types of cancer in the gastrointestinal tract (20). For men, eating watermelon has been shown to protect against prostate cancer (21).