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Watermelon is naturally delicious, so it has to be secretly terrible, right? Thankfully, the answer is no!

Fruit is not inherently dangerous, even for people with diabetes, but it affects everyone differently. So track your carbs, know a food’s glycemic index, and monitor your blood sugar so you know how a particular food affects you.

As long as you do that, you can enjoy foods like watermelon without worry.

To know how each food affects your blood sugar, it’s good to know where it ranks in terms of the glycemic index (GI) and glycemic load (GL).

The GI scale ranks foods based on how quickly they raise blood sugar. Foods that don’t cause blood sugar spikes rank 55 and under. Foods that quickly raise blood sugar are ranked 70 and higher.

Where does watermelon rank?

Sadly, watermelon is considered a high GI food, with a GI of 76. But don’t smash your melon dreams yet — some high GI foods don’t raise blood sugar as much as it may seem. That’s where the glycemic load comes in.

The GL takes into account the portion size of the food, as well as the GI. Carbs raise your blood sugar, and the number of carbs you consume is determined by the portion size.

That’s why the GL is a better indicator for how much a food will affect your blood sugar.

Watermelon has a low GL of 4.3 per 2 cups.

What does all this mean?

Basically, watermelon contains natural sugars that can raise blood sugar. But if you consume a small portion, like a cup of diced watermelon, then the effect on blood sugar is small.

In fact, people with diabetes may benefit from consuming small amounts of watermelon in moderation.

Not much research exists specifically on watermelon and diabetes, which is kind of mind-boggling, because who wouldn’t want to eat a bunch of watermelon in the name of science?

Anyway, there is growing evidence that watermelon may reduce complications from diabetes.

Meet lycopene

Lycopene is an antioxidant that occurs naturally in watermelon, tomatoes, and some other reddish fruits.

The lycopene found specifically in watermelon may help fight free radicals, slow cancer growth, and reduce the risk of cardiovascular disorders, diabetes, and macular diseases.

While lycopene won’t affect your blood sugar, it might reduce your risk of heart disease. This is important because 68 percent of people with diabetes over the age of 65 die of cardiovascular disease.

Bottom line

A hunk of watermelon won’t fix a heart, but keeping lycopene in your diet may have some positive effects.

Lifting a watermelon is no small effort! That’s because they’re jam-packed with vitamins and minerals.

What’s in a watermelon?

One cup of diced watermelon contains:

  • 43 calories
  • 0 g fat
  • 2 mg sodium
  • 11 g carbs
  • 9 g sugar
  • 1 g fiber

And the following percentage of daily vitamins:

  • 17 percent vitamin A
  • 21 percent vitamin C
  • 2 percent iron
  • 1 percent calcium

Other notable nutrients:

  • water
  • riboflavin
  • niacin
  • folate
  • magnesium
  • phosphorus
  • potassium
  • zinc
  • copper
  • manganese
  • choline
  • lycopene (more than is found in any other produce)

Tell me more

Watermelon contains vitamin C, which is known to improve heart health, help prevent some cancers, and battle the common cold.

What’s more, several small studies found that taking vitamin C supplements can lower post-meal blood sugar and reduce the risk for diabetes complications.

Watermelon has a full gram of fiber in every serving, which helps you lose weight, stay regular, and stay full. Soluble fiber also helps lower cholesterol and blood sugar, so it’s especially good for people with diabetes.

As if you weren’t sold on watermelon already, a recent study found that eating fresh watermelon daily significantly decreases body weight, body mass index (BMI), blood pressure, and waist-to-hip ratio — all of which are important factors for managing diabetes.

Pair it with a protein or healthy fat. Protein slows the absorption of sugar from the watermelon, preventing spikes.

Some ideas?

  • Add watermelon to a salad with some feta cheese and fresh mint.
  • Add half a cup of diced watermelon atop a cup of Greek yogurt.
  • Make chilled watermelon gazpacho.

Oh yeah — and it’s ok to eat the seeds, you won’t actually grow a watermelon in your stomach.

Though you can certainly enjoy fresh watermelon from time to time, there are other fruits with a lower GI that you can eat a lot more of.

And who doesn’t like a little extra? Apples, oranges, and plums are all low-GI fruits with lots of fiber and essential nutrients.

Feeling super glycemic adventurous? Try the lowest of the low — grapefruits or cherries. Cherries have a GI of only 20, so you can eat more of them, more often, without spiking your numbers.

Bottom line
  • All fruit is safe to eat if you have diabetes. Just be mindful of the glycemic index/glycemic load and how much fruit you’re regularly consuming in one sitting.
  • Pairing fruit with a protein or healthy fat to lower the effect on blood sugar is always a good idea.

Are there any fruits I should avoid?

Things get dicey when you process, juice, can, or dry fruits. This is because sugar is often added and healthy fibers are removed. Frozen fruit is fine, just make sure it doesn’t contain added sweeteners.

Bottom line: if you didn’t buy it in the produce aisle, check the label, watch for added sugar, and watch your portions.

Watermelon has a high GI and 21 grams of carbs per serving. On the flip side, it has a low GL, high concentrations of lycopene, vitamins A and C, and many other nutrients that are beneficial for those with diabetes.

Remember, the only way to really know how watermelon affects you is to check your blood sugar before and after eating it.