Grapefruit: A Nutritional Citrus Powerhouse
Grapefruit is a citrus fruit rich in various bioactive compounds. Its content includes flavonoids, flavanones, flavones, flavonols, and polymethoxylated flavones, with flavanones making up 98% of these compounds [1].
The primary flavanone in grapefruit, naringin, has gained attention for its effects on components of metabolic syndrome. These components include high blood sugar, high blood pressure, insulin resistance, and obesity. Additionally, furanocoumarins found in grapefruits and other citrus fruits exhibit biological activities such as anti-cancer, antioxidant, and anti-inflammatory properties [1].
Like other citrus fruits, grapefruit is rich in vitamins and minerals. However, it stands out as the only citrus fruit linked to body shaping and weight loss [2].
A 2014 study found significant metabolic benefits of grapefruit juice in mice fed a high-fat diet. The mice that consumed grapefruit juice experienced an 18.4% reduction in weight, a 13–17% decrease in fasting blood glucose, a threefold reduction in fasting insulin levels, and a 38% decrease in liver triglycerides compared to the control group. Additionally, the blood sugar-lowering effect of grapefruit juice was noted to be similar to that of metformin, a common diabetes medication. However, while naringin, the main bioactive compound in grapefruit juice, was effective in improving insulin resistance, it had no significant impact on preventing weight gain [2].
A systematic review and meta-analysis conducted in 2017 examined the effects of grapefruit juice on body weight and blood pressure. The findings revealed no significant impact on body weight but demonstrated a notable reduction in systolic blood pressure. However, the results were based on a limited number of controlled studies and short-term interventions, indicating the need for more extensive research [3].
Lastly, grapefruit juice and fruit have shown numerous positive effects on bone health and quality, including the prevention of osteoporosis [4].
[1] Khalil, M. N. A., Farghal, H. H., & Farag, M. A. (2020). Outgoing and potential trends of composition, health benefits, juice production and waste management of the multi-faceted Grapefruit Citrus Χ paradisi: A comprehensive review for maximizing its value. Critical Reviews in Food Science and Nutrition, 62(4), 935–956. [**https://doi.org/10.1080/10408398.2020.1830364**](https://doi.org/10.1080/10408398.2020.1830364) [2] Chudnovskiy, R., A. Thompson, K. Tharp, M. Hellerstein, J. L. Napoli, and A. Stahl. 2014. Consumption of clarified grapefruit juice ameliorates high-fat diet induced insulin resistance and weight gain in mice. PLoS One 9 (10):e108408. doi: 10.1371/journal.pone.0108408. [3] Onakpoya I, O’Sullivan J, Heneghan C, Thompson M. The effect of grapefruits (Citrus paradisi) on body weight and cardiovascular risk factors: A systematic review and meta-analysis of randomized clinical trials. Crit Rev Food Sci Nutr. 2017 Feb 11;57(3):602-612. doi: 10.1080/10408398.2014.901292. PMID: 25880021. [4] Deyhim, F., Mandadi, K., Patil, B. S., & Faraji, B. (2008). Grapefruit pulp increases antioxidant status and improves bone quality in orchidectomized rats. Nutrition, 24(10), 1039–1044. [**https://doi.org/10.1016/j.nut.2008.05.005**](https://doi.org/10.1016/j.nut.2008.05.005)
