Cucumber is a nutritious fruit with a high water content. Eating cucumber may help lower blood sugar, prevent constipation, and support weight loss. To maximize cucumber’s health benefits, eat the peel, too.

Though commonly thought to be a vegetable, cucumber is a fruit.

It’s high in beneficial nutrients, as well as certain plant compounds and antioxidants that may help treat and even prevent some conditions.

Cucumbers are also low in calories and contain a good amount of water and soluble fiber, making them ideal for promoting hydration and aiding in weight loss.

1. Cucumbers are nutrient-rich

Cucumbers are low in calories but high in many important vitamins and minerals.

One 10.62 ounce (301 gram) unpeeled, raw cucumber contains approximately:

  • Calories: 45
  • Total fat: 0.3 grams
  • Carbs: 11 grams
  • Protein: 2 grams
  • Fiber: 1.5 grams
  • Vitamin C: 8 grams
  • Vitamin K: 49 micrograms
  • Magnesium: 39 micrograms
  • Potassium: 442 milligrams
  • Manganese: 0.2 milligrams

Although the typical serving size is about one-third of a cucumber, eating a standard portion would provide about one-third of the nutrients above.

Cucumbers also have a high water content. They’re made up of about 96% water.

To maximize their nutrient content, cucumbers should be eaten unpeeled. Peeling them reduces the amount of fiber, as well as certain vitamins and minerals.

2. Cucumbers contain antioxidants

Antioxidants are molecules that block oxidation, a chemical reaction that forms highly reactive atoms with unpaired electrons known as free radicals.

The accumulation of these harmful free radicals can lead to several types of chronic illness.

Oxidative stress caused by free radicals has been associated with cancer and heart, lung, and autoimmune diseases.

Fruits and vegetables, including cucumbers, are especially rich in beneficial antioxidants that may reduce the risk of these conditions.

One 2015 study measured the antioxidant power of cucumber by supplementing 30 older adults with cucumber powder.

At the end of the 30-day study, cucumber powder caused a significant increase in several markers of antioxidant activity and improved antioxidant status.

However, it’s important to note that the cucumber powder used in this study likely contained a greater dose of antioxidants than you would consume in a typical serving of cucumber.

An older 2010 test-tube study investigated the antioxidant properties of cucumbers and found that they contain flavonoids and tannins, which are two groups of compounds that are especially effective at blocking harmful free radicals.

3. Cucumbers promote hydration

Water is crucial to your body’s function, playing numerous important roles. It involves processes like temperature regulation and transporting waste products and nutrients.

Proper hydration can affect everything from physical performance to metabolism.

While you meet most of your fluid needs by drinking water or other liquids, you may get as much as 40% of your water intake from food.

Fruits and vegetables, in particular, can be a good water source in your diet.

In one 2013 study, hydration status was assessed and diet records were collected for 442 children. They found that increased fruit and vegetable intake was associated with improved hydration.

Because cucumbers are about 96% water, they are especially effective at promoting hydration and can help you meet your daily fluid needs.

4. Cucumbers may aid in weight loss

Cucumbers could potentially help you lose weight in a few different ways.

First of all, they are low in calories. Each one-cup (104-gram) serving contains 16 calories, while an entire 11-ounce (300-gram) cucumber contains 45 calories.

This means you can eat plenty of cucumbers without packing on the extra calories that lead to weight gain.

Cucumbers can add freshness and flavor to salads, sandwiches, and side dishes and may be used as a replacement for higher-calorie alternatives.

Furthermore, the high water content of cucumbers could aid in weight loss as well.

One 2016 analysis looked at 13 studies involving 3,628 people overall and found that eating foods with high water and low calorie contents was associated with a significant decrease in body weight.

5. Cucumbers may help lower blood sugar levels

Several animal and test-tube studies have found that cucumbers may help reduce blood sugar levels and prevent some complications of diabetes.

A 2010 animal study induced diabetes in mice and supplemented them with cucumber peel extract. Cucumber peel reversed most of the diabetes-associated changes and caused a decrease in blood sugar.

In addition, one 2016 test-tube study found that cucumbers may be effective at reducing oxidative stress and preventing diabetes-related complications.

However, the current evidence is limited to test-tube and animal studies. Further research is needed to determine how cucumbers may affect human blood sugar.

6. Cucumbers may support regular bowel movements

Dehydration is a major risk factor for constipation, as it can alter your water balance and make the passage of stool difficult.

Cucumbers are high in water and promote hydration. Staying hydrated can improve stool consistency, prevent constipation, and help maintain regularity.

Moreover, cucumbers contain fiber, which helps regulate bowel movements.

In particular, pectin, the soluble fiber found in cucumbers, can help increase bowel movement frequency.

One 2014 study had 80 participants supplement with pectin. It found that pectin sped up the movement of the intestinal muscles, all while feeding the beneficial bacteria in the gut that improve digestive health.

The bottom line

Cucumbers can be a refreshing, nutritious, and versatile addition to any diet.

Mild with a distinctly crisp and refreshing flavor, cucumbers are commonly enjoyed fresh or pickled in everything from salads to sandwiches.

Cucumbers are also often eaten raw as a low calorie snack or can be paired with hummus, olive oil, lemon, or salad dressing to add flavor.