Is Watermelon Good for Weight Loss? Watermelon Diet Unveiled

Written by Nathan | Updated on 14 November 2021

If you’re looking to lose weight, you may be asking yourself, is watermelon good for weight loss? The internet is buzzing about the benefits of the watermelon diet. There are claims that it can detoxify your body and help you shed pounds quickly, but is it true? 

This summer’s favorite fruit touts plenty of nutritional benefits, which can include weight loss.

However, there are some considerations when deciding whether this diet is right for you. In this article, we go over the watermelon diet and what it offers so you can decide if it’s a weight loss technique that would fit your lifestyle.

The Watermelon Diet: Does It Work?

In short, the watermelon diet can work for weight loss because it’s a sure-fire way to create a caloric deficit. 

The diet comes in a few different versions, but the most extreme version is a cleanse. This form of the diet is incredibly restrictive and involves a strict period in which you eat nothing but watermelon for up to three days before going back to your normal diet or gradually introducing foods back into your diet for several days.

A 100-gram serving of watermelon has only 30 calories and the fruit is composed almost entirely of water, as the name suggests. For this reason, if you’re gorging on nothing but watermelon all day long, it would be difficult for you to eat enough of it to go over your suggested calorie budget [1]. 

Naturally, this means you’ll lose weight, especially if you’re incorporating exercise into your healthy lifestyle at the same time. So, the answer to whether watermelon is good for weight loss is yes, but another important question is whether using this weight loss method is good for your overall health.

You should also consider how long you should abide by this diet, which we’ll get into next.

Science Says Behind Watermelons & Weight Loss

Can you lose weight on a watermelon diet? The science says yes. According to a 2019 study, overweight adults who consumed 2 cups of fresh watermelon over 4 weeks saw several benefits, including lower hunger throughout the day and decreased bodyweight [2]. This study focused on a less extreme version of the watermelon weight loss diet and showed promising results, indicating that adding more watermelon into your diet is a good way to lose weight.

The more extreme version of this diet in which you eat only watermelon for 3 to 5 days is attractive to many people because it’s both very structured and has a short commitment time. Unlike a drastic and long-term lifestyle change, this diet is short-term enough that you might be more willing to stick to it because you get instant gratification and don’t have to punish yourself for very long [3].

For this reason, the watermelon diet cleanse might be a good choice for you if you want to kickstart your diet, but it’s not recommended to stick to this extreme diet long term because watermelon lacks key macronutrients like protein and carbohydrates that your body needs to function properly. 

Going too long without them can be detrimental to your health.

Benefits of Eating Watermelon to Lose Belly Fat

Is watermelon good for weight loss? Yes! It has several fantastic benefits that help you lose belly fat. Watermelon is:

  • Low-calorie – Watermelon is over 90% water, so by default, there isn’t much room for calories in one serving of it. With only 30 calories per serving, watermelon makes for a delicious snack that you don’t have to feel guilty about.
  • Hydrating – As previously mentioned, watermelon is jam-packed with water, making eating a serving more like drinking a yummy cup of water. Hydration is an often missed but crucial key to losing weight, so if you don’t like to drink water, adding watermelon to your diet is an effortless way to boost your hydration without having to think about it [4].
  • Satiating – The high water content is doubly effective because it helps you feel full after eating watermelon, too. This will help you be less likely to have the urge to snack between meals and should cut your overall cravings throughout the day.

Watermelon Nutrition Facts & Health Benefits

Watermelon isn’t just great for helping you lose weight. It’s also packed with several essential nutrients that contribute to multiple health benefits. These nutrients and their benefits include:

  • L- citrulline soothes muscle aches – Watermelon has more of this essential amino acid than any other food. It helps relax blood vessels and enhance circulation while getting rid of harmful ammonia from your body [5]. If you’re working out while losing weight, you’re going to deal with some soreness. This added perk from watermelon can help you feel less stiff the day after a tough workout.
  • Potassium promotes kidney health – Watermelon is full of this essential nutrient, which is great news for your renal system. Potassium plays a key part in flushing out toxins from your kidneys, so adding watermelon to any diet has the potential to help prevent kidney stones and keep your kidneys happy [6].
  • Lycopene promotes heart health – Lycopene is a powerful antioxidant that protects your body from harmful free radicals that can damage your heart and other parts of your body. Lycopene has also been linked to brain health, bone health, and preventing some cancers [2]. This makes it a powerhouse of a nutrient that your body will benefit greatly from when you incorporate watermelon into your diet.
  • Fiber is good for digestive health – The fiber in watermelon not only helps keep you full longer, but it’s also a key part of keeping your entire digestive tract healthy [7].
  • Vitamin C supports immune health – This vitamin is important for the growth and repair of all your body tissues and plays a key role in keeping your immune system and bones strong [8]. So adding watermelon to your diet during cold and flu season might prove to be extra beneficial.
  • B vitamins are essential nutrients – The B1 found in watermelon is important for helping your body break down food, and the B6 also found in this fruit plays an important role in creating red blood cells [9]. Eating enough of these vitamins can help you reduce the risk of anemia.
  • Vitamin A promotes eye health – This vitamin is necessary to convert the light that hits your eye into an electrical signal that’s sent to your brain to form an image. People who lack vitamin A in their diet are prone to night blindness and age-related eye disease. This vitamin may also have additional benefits such as its ability to lower your risk of certain cancers, reduce your risk of acne, supports bone health, and supports a healthy immune system [10].
  • Arginine helps reduce insulin resistance – This amino acid found in watermelon has been associated with helping prevent blood sugar spikes and the insulin resistance that can come with it. For this reason, eating watermelon might help prevent type 2 diabetes [11].
  • Magnesium and flavanols regulate blood pressure – These nutrients work together to keep your blood pressure normal. While Magnesium helps keep your blood pressure from dropping, flavonols help lower blood pressure [12, 13]. The combination will help your blood pressure stay in a healthy range. Flavanols have also been shown to improve blood flow, prevent blood clots, and fight cell damage [13].

5 Day Watermelon Diet Plan

To stay healthy while on a watermelon diet, it’s best that you still eat other foods. This way, you will still be getting some protein and other vital nutrients that aren’t in watermelon [14].

This diet puts participants in an extreme caloric deficit, which is usually not a healthy way to lose weight, and it can disrupt metabolic rates. Here’s an example meal plan if you were to try this diet, but always discuss diet changes with your healthcare provider first:   

Day 1

  • Breakfast:  2-5 whole-grain crackers, 1 slice of watermelon, and 1 cup of green tea or coffee
  • Lunch: 1 cup of watermelon and 100 g of lean boiled meat, like chicken
  • Dinner: 60-100 grams of cottage cheese and 1 cup of watermelon

Day 2

  • Breakfast: 1 slice whole-grain toast, 1 slice watermelon, and 1 cup green tea or coffee
  • Lunch: 100 grams lean boiled meat and 1 slice of watermelon
  • Dinner: 100 grams grilled fish like tilapia and 1 slice of whole-grain bread

Day 3

  • Breakfast: 1 slice whole-grain toast, 1 slice watermelon, and 1 cup low-fat milk
  • Lunch: 3 slices watermelon and 1 bowl of bean soup
  • Dinner: 2 slices watermelon and a vegetable salad with a vinaigrette dressing

Day 4

  • Breakfast: 2 slices watermelon, 1 egg, and 1 cup of green tea or coffee
  • Lunch: 1 slice whole-grain bread, 2 slices watermelon, and 1 bowl of low sodium chicken soup
  • Dinner: 3 medium boiled sweet potatoes

Day 5

  • Breakfast: 1 banana, 3 slices watermelon, and 1 cup coffee or tea
  • Lunch: 150 grams of slow roased, lean meat and as much watermelon as you want
  • Dinner: 60-100 g of cottage cheese and 1 slice of whole-grain bread

After finishing this 5-day diet, you’ll probably be able to see a clear answer to whether watermelon is good for weight loss based on your results.

You can slowly incorporate more protein and carbs into your meal plan until you’re meeting a healthy calorie goal for your BMI while still maintaining a caloric deficit. This way, you will continue to see results even after you’re done with the watermelon diet.

Watermelon Recipes

If you have no desire to go on a strict watermelon diet, but still want to reap the weight loss benefits of fruit like watermelon, a good way to do this is by incorporating watermelon into smoothies and juices. 

Not only are smoothies an easy way to add watermelon to your meal plan, but they’re perfect for adding tons of water, vitamins, and other nutrients from other fruits as well. As a bonus, you can use the sweet fruity taste of watermelon to cover up the taste of other nutritious foods you don’t like as much. 

Here is a simple smoothie recipe that you can experiment with to get optimal nutrition from your food:

Ingredients:

  • 1 cup chopped watermelon
  • 1 cup other fruit or veggies of choice
  • ½ cup water
  • 1 cup ice cubes

To make this smoothie, add all ingredients to a blender and blend until very smooth. Some flavor combinations you can try out are blackberries and coconut, banana and parsley, almond and peach, lime and basil, lemon and blueberries, and avocado and coconut.

If you want to detox your body, you may also want to try out a cucumber and watermelon diet drink. All you need for this is 2 cups watermelon, half of a cucumber, a sprig of mint, and ½ gallon of water. Place it all in a pitcher and add some ice and enjoy throughout the day.

Watermelon Pro Tips

To get the most out of the watermelon diet, do the following:

  • Don’t get pre-sliced watermelon. Certain nutrients start to break down after the fruit is sliced and exposed to oxygen [15]. For this reason, buy a whole watermelon fresh and slice it yourself. Freeze any extra and add it to smoothies you make throughout the week.
  • Try adding at least one watermelon smoothie into your meal plan every week for a healthy variety.
  • If you don’t want to drink your meal, try cutting up some watermelon and adding it to a salad with chopped onions and fresh feta cheese.
  • Try eating a slice of watermelon after a workout for hydration and electrolytes.
  • Enjoy a slice of watermelon as your evening treat instead of ice cream.

Potential Risks of the Watermelon Diet

Does watermelon help you lose body fat? It sure can. But there are also risks you should be aware of if you’re trying this diet. 

Consuming a lot of watermelons can lead to stomach upset and irritable bowel syndrome in some people. The high amount of fructose in this fruit is to blame for this problem, so anyone sensitive to FODMAPs – short-chain carbs that are poorly digested in the small intestine – should avoid this diet [16].

There is also a risk of allergy. Watermelon allergy is rare and is mostly associated with oral-allergy syndrome. If you do come down with a watermelon allergy, your symptoms might include swelling of the lips, tongue, and throat, as well as an itchy mouth and throat [17].

What Fruits Burn The Most Fat?

Watermelon is a great fat burner, but it’s not the only fruit that can help boost your weight loss. For the ultimate fat-burning meal plan, try adding these other weight loss promoting fruits:

  • Guava
  • Apple
  • Grapefruit
  • Banana
  • Tomato

All of these fruits have in common their high fiber content that helps you feel full longer. On top of that, they’re all packed with healthy vitamins and antioxidants that will boost your overall health.

FAQ

How Much Watermelon Should You Consume in a Day?

Try to aim for up to 300 g of watermelon a day for best results and to prevent unwanted digestive issues. Too much watermelon can be associated with increased blood sugar levels, overloaded liver, diarrhea, and even an orange discoloration of your skin thanks to the high lycopene content [18].  

There can be too much of a good thing with watermelon, so be careful not to eat too much.

When Should You Eat Watermelon for Weight Loss?

Eating watermelon in the morning is the best time. You may have seen some watermelon at night weight loss tips, but eating this fruit at night might not actually be the best idea. Because your digestive system slows down when you sleep, the digestive issues that fructose found in watermelons cause might be made worse if you eat a big bowl right before bed [19].

Furthermore, the huge amount of water in this fruit is likely to cause you to need frequent bathroom breaks, which isn’t good for your sleep. Eating watermelon in the morning will give you both a metabolism and hydration boost to start your day off right without the issues that can come from eating watermelon at night.

Can Watermelon Make You Fat?

Watermelon is not likely to make you fat. Since it takes 3,500 calories to make a pound of body fat, and there are only 30 calories in a serving of watermelon, you would have to eat a ton of it to gain weight from watermelon. 

Even though watermelon has sugar, it’s still considered to have a low glycemic load of only 4 on a scale of 20 [2]. For this reason, its effect on blood sugar is negligible and it won’t affect weight gain.

The Bottom Line

Watermelon is a great food choice for weight loss because it’s low-calorie, full of nutrients, and filling. Adding it into your diet can help you shed pounds fast. Still, the watermelon diet isn’t a permanent solution because it’s important to exercise regularly and eat other nutritional foods too. Remember, most foods are fine in moderation but it’s best to not take things to an extreme, especially when it can mess with your metabolism.

Resources

[1] Strasser, B., Spreitzer, A., & Haber, P. (2007). Fat Loss Depends on Energy Deficit Only, Independently of the Method for Weight Loss. Annals of Nutrition and Metabolism51(5), 428–432. https://doi.org/10.1159/000111162

[2] Lum, T., Connolly, M., Marx, A., Beidler, J., Hooshmand, S., Kern, M., Liu, C., & Hong, M. (2019). Effects of Fresh Watermelon Consumption on the Acute Satiety Response and Cardiometabolic Risk Factors in Overweight and Obese Adults. Nutrients11(3), 595. https://doi.org/10.3390/nu11030595

[3] Caleza, C., Yañez-Vico, R. M., Mendoza, A., & Iglesias-Linares, A. (2016). Childhood Obesity and Delayed Gratification Behavior: A Systematic Review of Experimental Studies. The Journal of Pediatrics169, 201–207.e1. https://doi.org/10.1016/j.jpeds.2015.10.008

[4] Thornton, S. N. (2016). Increased Hydration Can Be Associated with Weight Loss. Frontiers in Nutrition3. https://doi.org/10.3389/fnut.2016.00018

[5] Allerton, T., Proctor, D., Stephens, J., Dugas, T., Spielmann, G., & Irving, B. (2018). l-Citrulline Supplementation: Impact on Cardiometabolic Health. Nutrients10(7), 921. https://doi.org/10.3390/nu10070921

[6] Office of Dietary Supplements – Potassium. (2021, March 26). NIH. https://ods.od.nih.gov/factsheets/Potassium-Health%20Professional/

[7] Myhrstad, M. C. W., Tunsjø, H., Charnock, C., & Telle-Hansen, V. H. (2020). Dietary Fiber, Gut Microbiota, and Metabolic Regulation—Current Status in Human Randomized Trials. Nutrients12(3), 859. https://doi.org/10.3390/nu12030859

[8] Office of Dietary Supplements – Vitamin C. (2021, March 26). NIH. https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/

[9] B Vitamins. (2020, August 11). The Nutrition Source. https://www.hsph.harvard.edu/nutritionsource/vitamins/vitamin-b/

[10] Office of Dietary Supplements – Vitamin A. (2021, March 26). NIH. https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/

[11] Kuryata, O., & Sirenko, O. (2017). Endothelial Function, Insulin Resistance, Serum Adiponectin Level in Rheumatoid Arthritis Females with Renal Dysfunction and Its Dynamics with L-Arginine Aspartate Supplementation. La Prensa Medica103(6). https://doi.org/10.4172/lpma.1000269

[12] Houston, M. (2011). The Role of Magnesium in Hypertension and Cardiovascular Disease. The Journal of Clinical Hypertension13(11), 843–847. https://doi.org/10.1111/j.1751-7176.2011.00538.x

[13] Davison, K., Berry, N. M., Misan, G., Coates, A. M., Buckley, J. D., & Howe, P. R. C. (2010). Dose-related effects of flavanol-rich cocoa on blood pressure. Journal of Human Hypertension24(9), 568–576. https://doi.org/10.1038/jhh.2009.105

[14] Klein, A. V., & Kiat, H. (2014). Detox diets for toxin elimination and weight management: a critical review of the evidence. Journal of Human Nutrition and Dietetics28(6), 675–686. https://doi.org/10.1111/jhn.12286

[15] Gil, M. I., Aguayo, E., & Kader, A. A. (2006). Quality Changes and Nutrient Retention in Fresh-Cut versus Whole Fruits during Storage. Journal of Agricultural and Food Chemistry54(12), 4284–4296. https://doi.org/10.1021/jf060303y

[16] Gearry, R., Skidmore, P., O’Brien, L., Wilkinson, T., & Nanayakkara, W. (2016). Efficacy of the low FODMAP diet for treating irritable bowel syndrome: the evidence to date. Clinical and Experimental Gastroenterology, 131. https://doi.org/10.2147/ceg.s86798

[17] Pastor, C., Cuesta-Herranz, J., Cases, B., Pérez-Gordo, M., Figueredo, E., de las Heras, M., & Vivanco, F. (2009). Identification of Major Allergens in Watermelon. International Archives of Allergy and Immunology149(4), 291–298. https://doi.org/10.1159/000205574

[18] Rudd, E. C., & Merika, E. E. (2020). Carotenoderma caused by excessive watermelon and red grapefruit consumption. Clinical and Experimental Dermatology45(8), 1093–1095. https://doi.org/10.1111/ced.14315

[19] DiNicolantonio, J. J., & Lucan, S. C. (2015). Is fructose malabsorption a cause of irritable bowel syndrome? Medical Hypotheses85(3), 295–297. https://doi.org/10.1016/j.mehy.2015.05.019

About the Author

Nathan

Nathan has been a fitness enthusiast for the past 12 years and jumps between several types of training such as bodybuilding, powerlifting, cycling, gymnastics, and backcountry hiking. Due to the varying caloric needs of numerous sports, he has cycled between all types of diets and currently eats a whole food diet. In addition, Nathan lives with several injuries such as hip impingement, spondylolisthesis, and scoliosis, so he underwent self-rehabilitation and no longer lives with debilitating pain.