Two studies looked at the effects of watermelon on diet quality and cardiometabolic function. They found that watermelon consumption is linked to higher nutrient intake and better heart health. More research is needed to understand how watermelon affects cardiometabolic health. Watermelon contains many nutrients, such as potassium, vitamin C and magnesium. The fruit also exhibits high bioavailability of antioxidants, including lycopene and l-citrulline.

Studies have shown that watermelon supplements and extracts reduce blood pressure and cholesterol levels. The number of studies looking at raw watermelon is comparatively smaller, and those that do usually look at large amounts, greater than 1 kg per day. Nevertheless, these studies also indicate that consumption of this fruit is linked to lower cholesterol levels and body weight, as well as a reduced risk of prostate, lung and breast cancer.

Further study of the health effects of raw watermelon could help improve dietary recommendations and preventive strategies for cardiometabolic health.
Recently, two studies have looked at the health effects of watermelon consumption.

The first study, published in Nutrients, showed that children and adults who ate watermelon had higher intakes of various nutrients, including dietary fiber, magnesium and potassium, than those who did not. They also consumed less added sugars and saturated fatty acids. The second study, also published in Nutrients, showed that drinking watermelon juice for two weeks protected vascular function.

As the warm summer months approach, these two studies suggest that regular consumption of watermelon could be beneficial for you! In fact, excessive consumption probably wouldn’t have ill effects, unlike so many other things we enjoy.

Watermelon eaters could have a healthier diet

For the first study, researchers analyzed data from 56,133 people from the National Health and Nutrition Examination Survey (NHANES). They collated data between 2003 and 2018, and included two 24-hour dietary recalls from individuals aged 2 to 18, as well as adults. The average consumption of watermelon among adults and children was 125 and 162 grams per day. About 98% of participants consumed raw watermelon, while 2% consumed watermelon juice. By analyzing dietary information, researchers were able to estimate overall nutrient intake among watermelon consumers and non-consumers. To ensure the accuracy of their results, they controlled for factors such as physical activity, income poverty ratio (PRR), smoking and alcohol consumption. They also controlled for consumption of other foods, including the total number of vegetables, fruit other than watermelon, and consumption of dairy products.

In the end, they found that watermelon consumers, children and adults, had more than 5% higher consumption of:

dietary fiber
vitamin A
Their intake of added sugars and total saturated fatty acids was also 5% lower, and their intake of lycopene and other carotenoids was higher. The researchers noted that their findings show watermelon consumption may also be linked to adherence to general dietary recommendations. People who eat watermelon and other fruits probably do so to satisfy their sweet tooth. By eating fruit, they consume less processed products which often contain high fructose corn syrup.

The impact of watermelon on cardiometabolic health

In the second study, researchers sought to better understand the biological mechanisms underlying watermelon’s beneficial health effects. Autonomic dysfunction, which occurs when the nerves of the autonomic nervous system are damaged, is linked to the development of cardiometabolic diseases. Heart rate variability (HRV), the variation of two consecutive heartbeats, is a simple and reliable method to assess autonomic dysfunction. Consuming large amounts of sugar has been shown to reduce HRV, vascular function, and microvascular blood flow. These effects are thought to be due to a reduction in the bioavailability of nitric oxide (NO).

The amino acid L-citrulline converts to L-arginine in the body, which promotes the formation of NO. Studies have shown that NO-promoting therapies, especially nitrates
and beet juice, may improve HRV.

Because watermelon is high in L-citrulline and L-arginine, researchers investigated the effect of drinking watermelon juice on HRV after high glucose intake. To do this, they recruited 18 healthy men and women, with an average age of 23 and an average weight of 67 kg. Participants were randomly assigned to drink either 500ml watermelon juice or a placebo every day for two weeks. In the end, the researchers found that watermelon juice consumption protects against HRV impairment following high sugar consumption.

Although watermelon juice is known to contain high amounts of nitric acid precursors, it also contains antioxidants (like vitamin C) that can also affect nitric oxide. For this reason, the exact mechanism of action of watermelon juice in controlling heart rate variability was not clearly defined in this study.

Health Effects of Watermelon Consumption

Some might not consider watermelon as part of a heart-healthy diet due to its high sugar content. However, the sugars in this fruit are low on the glycemic index, which means they have less of an impact on blood sugar levels than sugars from other sources. Additionally, the high fiber and water content of the fruit may also lessen the effects on blood sugar when consumed in moderation. In addition, watermelon contains a variety of heart-healthy bioactive compounds. Lycopene, for example, has antioxidant properties and has been linked to a reduced risk of cardiovascular diseases, such as coronary heart disease and stroke.

The high potassium content of watermelon can help regulate blood pressure. The high water content guarantees good hydration. Adequate hydration is essential to indirectly maintain blood viscosity and reduce thrombosis. The vitamin C contained in watermelon contributes to endothelial health and the maintenance of the integrity of blood vessels. Watermelon contains a host of other vitamins and minerals that may have beneficial effects on the cardiovascular system, including beta-carotene, vitamin B6, magnesium, and folic acid.

Fruit should be part of a healthy diet

Eat more fruit each day, especially watermelon and citrus fruits. It is important to consider daily fruits as an important part of the diet because they are full of antioxidants, anti-inflammatories, dietary fiber and water, all of which can improve cardiovascular function, function brain, skin function and reduce certain cancers.

Fruit also improves digestive health, boosts energy and improves mood. Remember the old saying “an apple a day keeps the doctor away”, but now apply it to all fruits: “a few fruits a day keeps the doctor away”.

If research conducted under proper design and methodology remains positive regarding the consumption of watermelon and its beneficial effects on the cardiovascular system, this food could become a mainstay of a healthy diet for the heart, not least because of its wide availability and affordability.

* criptom strives to transmit health knowledge in a language accessible to all. In NO CASE, the information given can not replace the advice of a health professional.