A stronger immune system, lower cholesterol levels and even weight loss are just a few of the benefits of grapefruit. This citrus fruit and its juice are rich in antioxidants that protect your body from free radicals. Eating too much grapefruit is unlikely to cause side effects other than digestive discomfort. However, certain compounds in grapefruit can interact with prescription and OTC drugs, putting you at risk for kidney failure and organ damage, as reported by the FDA.
Nutritional Benefits of Grapefruit
This tropical citrus fruit is known for its high content of vitamin C and antioxidants. It's surprisingly low in calories and can be used in a multitude of recipes, from fresh juices and smoothies to desserts and savory dishes.
Depending on your preferences, you can make broiled grapefruit with cinnamon, high-protein cookies with grapefruit, roasted salmon with grapefruit sauce, pink grapefruit sorbet and other delicious treats. You can even add grapefruit to quinoa salad, pie or homemade energy bars.
But, what makes grapefruit so special? First of all, it has only 65 calories per serving. One serving of apples, by comparison, boasts 84 calories. Watermelon has 84 calories per serving, too. Grapefruit is lower in calories than most fruits, making it ideal for dieters.
One serving of grapefruit is 5.4 ounces — that's enough to fill you up and curb hunger. The fiber in this fruit will further suppress your appetite and help reduce your daily food intake. Grapefruit also provides more than half of the daily value (DV) of vitamin C, keeping your immune system strong. A single serving contains:
- 65 calories
- 16.4 grams of carbs
- 1.1 grams of protein
- 0.2 grams of fat
- 2.5 grams of fiber
- 10.6 grams of sugars
- 53 percent of the DV of vitamin C
- 10 percent of the DV of vitamin A
- 10 percent of the DV of beta-carotene
- 5 percent of the DV of folate
- 4 percent of the DV of potassium
- 3 percent of the DV of magnesium
Grapefruit juice is just as healthy, offering large doses of flavonoids, magnesium, potassium, vitamin C and citric acid. Surprisingly, the peel is a powerhouse of nutrition too, according to a review published in Oxidative Medicine and Cellular Longevity in January 2016.
Read more: How to Drink Grapefruit Juice to Lose Weight
Researchers have found that dried grapefruit peel is chock-full of polyphenols, flavonoids and other bioactive compounds. These chemicals fight oxidative stress and modulate neuronal activities, such as mood, cognition and brain plasticity.
The above review points out that fresh grapefruit peel is higher in naringin compared to dried peels. This flavonoid has been studied for its beneficial effects on the liver.
An April 2018 review featured in the World Journal of Gastroenterology suggests that naringin protects the liver from oxidative damage and may help in the treatment of liver disease through the regulation of lipid metabolism and cholesterol oxidation, despite its low bioavailability. More studies are needed to confirm its therapeutic potential, however.
Are There Safety Concerns?
Grapefruit detox plans, grapefruit juice diets and liver cleansing protocols are all the rage nowadays — not to mention the popular grapefruit diet, which has been around for decades. Despite its health benefits, grapefruit isn't a cure-all and should not be treated as such. In fact, it can do more harm than good when consumed in large amounts or along with certain drugs.
First of all, grapefruit is high in citric acid, a naturally occurring compound that gives citrus fruits their sour taste. As the Cleveland Clinic points out, citrus fruits and citrus juices may cause heartburn or make it worse. If you eat too many grapefruits, you may experience chest pain, burning in the throat and chest, acidic or bitter taste in the mouth and other heartburn symptoms.
Read more: The 10 Worst Foods for Acid Reflux
This fruit might not be the best choice for people with irritable bowel syndrome, or IBS. This gastrointestinal condition affects 10 to 15 percent of the world's population, according to the International Foundation for Gastrointestinal Disorders. About 40 percent of sufferers have mild IBS, while 25 percent report severe symptoms that interfere with their daily lives. Bloating, gas, stomach pain and altered bowel behaviors are all common symptoms.
As the Canadian Society of Intestinal Research notes, citrus fruits may cause digestive problems in some IBS sufferers. These foods can irritate the stomach and worsen your symptoms.
Additionally, grapefruit is rich in fiber. When consumed in excess, this nutrient may cause bloating, gas, diarrhea or constipation, abdominal pain and decreased appetite. It can also bind iron, zinc, magnesium and other minerals, leading to nutrient deficiencies. Grapefruit alone is unlikely to cause these problems, but if your diet is already high in fiber, it may cause digestive distress (when consumed in large amounts).
Read more: 10 Ways to Beat Belly Bloat
Grapefruit Can Interact With Medications
According to the NHS, grapefruit and prescription drugs are a deadly mix. Furanocoumarins, a group of chemicals in this fruit, can cause some medications to enter your body faster, increasing the risk of side effects. Grapefruit juice, lime, pomelo and other citrus fruits contain these chemicals, too. A March 2013 review published in the Canadian Medical Association Journal (CMAJ) confirms these findings.
The review authors state that one whole grapefruit or 6.7 ounces of grapefruit juice is enough to increase drug concentration in the bloodstream. For example, taking calcium inhibitors with grapefruit juice may cause toxicity in the kidneys.
Grapefruit can interact with more than 85 drugs, according to the NHS, including statins, corticosteroids, anti-anxiety medications, antihistamines, antihypertensives, calcium channel blockers and psychiatric medications, as reported by Harvard Health Publishing.
If you're taking any of these medications, you might not be able to enjoy the health benefits of grapefruit. However, there are other ways to get more fiber, antioxidants and vitamin C into your diet. Navel and Valencia oranges, for instance, don't contain furanocoumarins, according to the CMAJ.
These fruits have a similar nutritional profile to grapefruit. Navel oranges provide 75 calories, 19 grams of carbs and 3.4 grams of fiber per serving. They also deliver a whopping 101 percent of the daily recommended vitamin C intake.
California Valencia oranges, by comparison, are lower in vitamin C but have just 59 calories and 14.4 grams of carbs per serving. Additionally, these juicy citrus fruits offer 3 grams of fiber and high doses of copper, magnesium, calcium and folate.
Grapefruit is otherwise safe for healthy individuals. Just remember to enjoy it in moderation. Consider replacing soft drinks with grapefruit juice to cut calories and boost your antioxidant intake.
- FDA: "Grapefruit Juice and Some Drugs Don't Mix"
- USDA: "Raw Grapefruit"
- USDA: "Apples, Raw, Granny Smith, With Skin"
- USDA: "Raw Watermelon"
- Joslin Diabetes Center: "How Does Fiber Affect Blood Glucose Levels?"
- USDA: "Nutrition Facts for Pink Grapefruit"
- NCBI: "Grapefruit Juice Nutritional Profile"
- Hindawi: "Bioactive Flavonoids, Antioxidant Behaviour, and Cytoprotective Effects of Dried Grapefruit Peels (Citrus paradisi Macf.)"
- NCBI: "Beneficial Effects of Naringenin in Liver Diseases: Molecular Mechanisms"
- Cleveland Clinic: "Heartburn Overview"
- International Foundation of Gastrointestinal Disorders: "IBS Statistics"
- Canadian Society of Intestinal Research: "IBS Diet: The Foods You Can Eat"
- Duke.edu: "Fiber-How"
- NHS: "Prescription Drugs and Grapefruit - A Deadly Mix"
- CMAJ: "Grapefruit–Medication Interactions: Forbidden Fruit or Avoidable Consequences?"
- Harvard Health Publishing: "Grapefruit and Medication: A Cautionary Note"
- USDA: "Nutrition Facts for Navel Oranges"
- USDA: "Nutrition Facts for California Valencia Oranges"
- Weight Control Information Network; Weight-Loss and Nutrition Myths; March 2009
- "The New York Times"; Can Grapefruit Increase the Risk of Breast Cancer?; A. O'Connor; March 2008