Grapefruit

Grapefruit

Grapefruit is a citrus fruit known for its sour to semi-sweet taste. Possibly a cross between an orange and a pomelo, this nutritious fruit doesn’t only contain vitamin C. It is also loaded with vitamin A, B complex, E and K. In the mineral department, decent amounts of calcium, folate, potassium, and phosphorus are found in grapefruit. Therefore, consuming raw grapefruit or taking it as supplements can improve your overall health and prevent a wide array of medical maladies.

Benefits of Grapefruit

An overwhelming body of high quality studies supports the medicinal properties of this nutrient powerhouse. Among its diverse health benefits, the following are worth mentioning:

Prevents Cognitive Decline

A 2014 study published in the Neural Regeneration Research found that patients with cognitive impairment related to Parkinson’s disease who were treated with naringin, a well-known flavonoid from grapefruit, experienced an improvement in memory and thinking skills.[1] Researchers found that the treatment significantly increased the levels of glial cell line-derived neurotrophic factor (GDNF), a protein that potently promotes the survival of many types of nerve cells in the brain.

Helps Lose Weight

While grapefruits are sweet, they are actually very low in calories and they can be added to your weight loss regimen. According to a 2006 study published in the Journal of Medicinal Food, grapefruit consumption can be beneficial in obese patients who are trying to lose weight.[2] Researchers found that after 12 weeks of treatment, patients who ate grapefruit had lost 1.6 kg, patients who drank grapefruit juice had lost 1.5 kg, patients who took grapefruit capsule had lost 1.1 kg, and patients who took placebo had lost only 0.3 kg.

Prevents Insulin Resistance and Diabetes

Insulin resistance occurs when your body stops responding to the effects of insulin, a hormone that helps lower blood sugar levels. Insulin resistance ultimately leads to elevated blood sugar levels – both of which are major risk factors for type 2 diabetes. Eating grapefruit may help normalize blood sugar levels and reduce the likelihood of becoming insulin resistant. In one study, subjects who consumed half of a fresh grapefruit three times a day before each meal reduced their blood sugar levels significantly compared to those who took placebo, suggesting that grapefruit consumption has anti-diabetic effect.[2]

Boosts Immune Function

The immune-boosting effect of grapefruit is attributed to its high vitamin C content. Several studies suggest that vitamin C from grapefruit can help combat a broad range of infections including common cold, by enhancing the activities of several cells of the immune system, thereby triggering a heightened immune response.[3-6]

Improves Blood Pressure and Cholesterol Levels

A 2012 study assessing the effects of grapefruit consumption on lipids and blood pressure levels found that healthy, overweight adults who consumed grapefruit with each meal (3x daily) for 6 weeks experienced a significant reduction in blood pressure and cholesterol levels.[7] Aside from these beneficial effects, the researchers also observed that grapefruit consumption has no adverse side effects.

Prevents Kidney Stones

Larger kidney stones known as calcium oxalate stones may block the flow of urine, which can lead to excruciating pain. Citric acid, an organic acid found in grapefruit, may help prevent kidney stones by binding with calcium to flush them out of the body and increasing the volume and pH of your urine to produce an environment that is less favorable to the formation of these stones.[8-10]

References:

1. Jung UJ, Kim SR. Effects of naringin, a flavanone glycoside in grapefruits and citrus fruits, on the nigrostriatal dopaminergic projection in the adult brain. Neural Regeneration Research. 2014;9(16):1514-1517. doi:10.4103/1673-5374.139476.
2. Fujioka K, Greenway F, Sheard J, Ying Y. The effects of grapefruit on weight and insulin resistance: relationship to the metabolic syndrome. Journal of medicinal food. 2006; 9(1):49-54.
3. Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. The Cochrane database of systematic reviews. 2013.
4. Douglas RM, Hemilä H, Chalker E, Treacy B. Vitamin C for preventing and treating the common cold. The Cochrane database of systematic reviews. 2007.
5. Ströhle A, Hahn A. [Vitamin C and immune function]. Medizinische Monatsschrift fur Pharmazeuten. 2009; 32(2):49-54; quiz 55-6.
6. Fashner J, Ericson K, Werner S. Treatment of the common cold in children and adults. American family physician. 2012; 86(2):153-9.
7. Dow CA, Going SB, Chow HH, Patil BS, Thomson CA. The effects of daily consumption of grapefruit on body weight, lipids, and blood pressure in healthy, overweight adults. Metabolism: clinical and experimental. 2012; 61(7):1026-35.
8. Caudarella R, Vescini F. Urinary citrate and renal stone disease: the preventive role of alkali citrate treatment. Archivio italiano di urologia, andrologia : organo ufficiale [di] Societa italiana di ecografia urologica e nefrologica. 2009; 81(3):182-7.
9. Phillips R, Hanchanale VS, Myatt A, Somani B, Nabi G, Biyani CS. Citrate salts for preventing and treating calcium containing kidney stones in adults. The Cochrane database of systematic reviews. 2015.
10. Gul Z, Monga M. Medical and Dietary Therapy for Kidney Stone Prevention. Korean Journal of Urology. 2014;55(12):775-779. doi:10.4111/kju.2014.55.12.775.