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- Nutrition and Metabolism; Effects of Grapefruit, Grapefruit Juice and Water; Heidi Silver; February 2011
- Ace Fitness: Diet Myths Debunked
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Does Drinking Grapefruit Juice After Meals Help You Lose Weight?
Each year, over 50 million Americans go on a diet, but only 5 percent maintain their weight loss, according to Colorado State University. In the quest for quick and convenient weight loss solutions, consumers often choose between plans that require no dietary sacrifice or lifestyle change and programs with extreme dietary restrictions and rigid time-consuming workout plans. The former produces no lasting results and the latter usually is impossible to maintain. Grapefruit juice appears to be an alternative that promotes weight loss at a consistent, maintainable level independent of other dietary or lifestyle changes.
Scripps Clinic Study
A 12-week study conducted by Scripps Clinic in San Diego, California, observed the effects of consuming both grapefruit and grapefruit juice. One hundred men and women were segregated into two groups, and one group ate half a grapefruit with each meal while the other group drank one serving of grapefruit juice with their meals. At the end of 12 weeks, the subjects who ate grapefruit lost an average of 3.6 lbs. while the participants who drank grapefruit juice typically lost 3.3 lbs. While these are median numbers, it’s worth noting that some subjects lost more than 10 lbs. during the study.
- A 12-week study conducted by Scripps Clinic in San Diego, California, observed the effects of consuming both grapefruit and grapefruit juice.
- At the end of 12 weeks, the subjects who ate grapefruit lost an average of 3.6 lbs.
Vanderbilt University Study
Substitute for Grapefruit in the Grapefruit Diet
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Researchers at Vanderbilt University conducted a 14-week study to determine the effectiveness of grapefruit, grapefruit juice and water as a pre-meal weight-loss solution in obese adults 1. Participants were put on a reduced calorie diet and instructed to consume half a grapefruit, half a cup of grapefruit juice or half a cup of water before their three main meals each day. Fourteen weeks later, each of the groups lost an average of 15 pounds. However, the groups consuming grapefruit or grapefruit juice experienced the additional health benefits of significantly escalating their HDL, or “good,” cholesterol levels while also increasing their vitamin C and fiber intake levels.
- Researchers at Vanderbilt University conducted a 14-week study to determine the effectiveness of grapefruit, grapefruit juice and water as a pre-meal weight-loss solution in obese adults 1.
- However, the groups consuming grapefruit or grapefruit juice experienced the additional health benefits of significantly escalating their HDL, or “good,” cholesterol levels while also increasing their vitamin C and fiber intake levels.
University of Western Ontario Study
The research team at the University of Western Ontario studied the results of a grapefruit flavonoid on laboratory mice. The mice were divided into two groups and given a steady diet of sugary and fatty foods, but, in the group fed the grapefruit molecule, fatty buildup was reduced by 80 percent, and cholesterol and triglyceride levels decreased. However, the researchers caution that this does not prove the effectiveness of grapefruit diets since humans would need to consume six to eight glasses of grapefruit juice a day to achieve comparable results.
Naysayers
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Despite the research, opinions vary on the effectiveness of grapefruits as a weight-loss tool. Tufts University acknowledges the Scripps study but warns it was conducted with a small group of subjects and additional research is needed. The university recommends eating at least three fruit servings daily but suggests variety. Ace Fitness cautions against the grapefruit diet, lemon juice diet and other programs that focus on a single ingredient found in certain foods 6.
- Despite the research, opinions vary on the effectiveness of grapefruits as a weight-loss tool.
- Tufts University acknowledges the Scripps study but warns it was conducted with a small group of subjects and additional research is needed.
Related Articles
References
- Medical News Today; Grapefruit and Weight Loss; January 2004
- PRNewswire; New Research Suggests Grapefruit Can Play a Role in Weight Loss; April 2011
- Nutrition and Metabolism; Effects of Grapefruit, Grapefruit Juice and Water; Heidi Silver; February 2011
- The Star.com; Grapefruit Glory; Joseph Hall; July 2009
- Tufts Medical Center: Grapefruit Diet
- Ace Fitness: Diet Myths Debunked
- Scutts J. The Depression Era’s Magic Bullet For Weight Loss. The New Republic. Published May 27, 2016.
- Mugnolo C. What You Should Know About the Unofficial Mayo Clinic Grapefruit Diet. Livestrong.com. Updated September 17, 2019.
- Thomson TL. Ahrens JM. The Grapefruit Solution: Lower Your Cholesterol, Lose Weight and Achieve Optimal Health with Nature's Wonder Fruit. Carlsbad, California: LINX Corporation; 2004.
- Woman's World. The Grapefruit Diet Hack That Blasts Belly Bulge in Days. August 16, 2019
- Diet.com. Grapefruit diet.
- Picincu A. Livestrong.com. 21 Day Grapefruit Diet. Updated June 10, 2019.
- Beth Israel Lahey Health Winchester Hospital. Health Library - Grapefruit Diet. Updated June 16, 2017.
- Murphy MM, Barraj LM, Rampersaud GC. Consumption of grapefruit is associated with higher nutrient intakes and diet quality among adults, and more favorable anthropometrics in women, NHANES 2003-2008. Food Nutr Res. 2014;58. doi:10.3402/fnr.v58.22179
- Bailey DG, Dresser G, Arnold JM. Grapefruit-medication interactions: forbidden fruit or avoidable consequences?. CMAJ. 2013;185(4):309-16. doi:10.1503/cmaj.120951
- Colucci P, Yue CS, Ducharme M, Benvenga S. A Review of the Pharmacokinetics of Levothyroxine for the Treatment of Hypothyroidism. Eur Endocrinol. 2013;9(1):40-47. doi:10.17925/EE.2013.09.01.40
- Lee JW, Morris JK, Wald NJ. Grapefruit Juice and Statins. Am J Med. 2016;129(1):26-9. doi:10.1016/j.amjmed.2015.07.036
- El-Hage W, Samuel L, Vincent C, Catherine B. Mechanisms of antidepressant resistance. Front Pharmacol. 2013;4:146. doi:10.3389/fphar.2013.00146
- Murphy MM, Barraj LM, Rampersaud GC. Consumption of grapefruit is associated with higher nutrient intakes and diet quality among adults, and more favorable anthropometrics in women, NHANES 2003-2008. Food Nutr Res. 2014;58. doi:10.3402/fnr.v58.22179
- U.S. Department of Agriculture. Grapefruit, raw, pink and red, all areas. Updated April 1, 2019.
- Fujioka K, Greenway F, Sheard J, Ying Y. The effects of grapefruit on weight and insulin resistance: relationship to the metabolic syndrome. J Med Food. 2006;9(1):49-54. doi:10.1089/jmf.2006.9.49
- Abdul hakim BN, Yahya HM, Shahar S, Abdul manaf Z, Damanhuri H. Effect of Sequence of Fruit Intake in a Meal on Satiety. Int J Environ Res Public Health. 2019;16(22). doi:10.3390/ijerph16224464
- 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;57(3):602-612. doi:10.1080/10408398.2014.901292
- Buddemeyer KM, Alexander AE, Secor SM. Negative calorie foods: An empirical examination of what is fact or fiction. bioRxiv. doi:10.1101/586958
- U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015–2020 Dietary Guidelines for Americans. 8th Edition. Published December 2015.
- Foley KE. Quartz. A short history of terrible diets. September 1, 2018
- Bertoia ML, Mukamal KJ, Cahill LE, et al. Changes in Intake of Fruits and Vegetables and Weight Change in United States Men and Women Followed for Up to 24 Years: Analysis from Three Prospective Cohort Studies. PLoS Med. 2015;12(9):e1001878. doi:10.1371/journal.pmed.1001878
- Thompson C. Livestrong.com. What Is the Egg Diet, and Can It Help You Lose Weight?. Updated January 30, 2020.
- Academy of Nutrition and Dietetics. Staying Away from Fad Diets. March 18, 2019.
- Harvard Health Publishing. Calorie counting made easy.
- LaMotte S. CNN Health. Military diet: 3-day diet or dud?. March 8, 2018.
- Rettner R. HuffPost. M Plan, New Mushroom Diet Promising Selective Weight Loss, Won’t Work, Experts Say. September 9, 2013.
Writer Bio
Terri Williams began writing professionally in 1997, serving as media manager for a large nonprofit organization where she also edited books and created promotional content. She has written extensively on business communication, ethics, leadership, management, education and health. Williams has a Bachelor of Arts in English from the University of Alabama at Birmingham.