The role white and pink (red) grapefruit may play in weight loss and cholesterol control, as well as the suppression of drug-clearance enzymes within the body.
Tell Your Doctor if You Eat Grapefruit
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
If you have people eat half a grapefruit three times a day before each meal for a couple months, they may lose about two pounds. But, that’s no more than if they ate three apples or pears a day. In this study, the grapefruit-eaters not only saw their weight go down, but their waist got slimmer, and their body fat melted away. If, however, you repeat the experiment, and instead ask people to drink a half-cup of water before each meal, you get the same result. So, this belief that grapefruit has some special fat-burning quality appears to be just a “long-held myth.”
Here’s the latest, showing grapefruit consumers had a drop in weight, significant drop in cholesterol, significant drop in blood pressure. “Conclusion: This study suggests that consumption of grapefruit daily for 6 weeks does not significantly decrease body weight, cholesterol, or blood pressure.” What?! That made me do a little double take. But again, it’s because the grapefruit just didn’t do any better than placebo.
Other studies have found a legitimate cholesterol-lowering benefit—especially eating red, as opposed to white, grapefruits—and, even a little dip in triglycerides. This was one grapefruit a day for 30 days. But, as you can see, though, they went from one life-threatening cholesterol level to another life-threatening cholesterol level. To prevent heart disease, you really have to get down to a total cholesterol of around 150—the average cholesterol of those eating diets composed exclusively of plant foods, not just grapefruits.
Even though grapefruits alone don’t do much, the researchers suggest that people might be more likely to stick with them than cholesterol-lowering drugs, noting that most people with heart disease stop taking their statin drugs within a couple years, because of the adverse side effects, whereas grapefruit alone don’t have any side effects. But, ironically, combine grapefruits and drugs together, and you can make drug side effects even worse.
Now, hopefully, if you eat lots of fruits and veggies, you won’t need a lot of drugs. But, certain phytochemicals in plants can affect the metabolism of drugs in the body, and grapefruit is the poster child—described as “a pharmacologist’s nightmare.” Natural phytochemicals in grapefruit suppress the enzymes that help clear more than half of commonly prescribed drugs, and so, less drug clearance means higher drug levels in the body. Now, this may be good, if you want a better caffeine buzz from your morning coffee, or your doctor wants to help you save thousands of dollars boosting the effects of expensive drugs, instead of just peeing them down the toilet.
But, higher drug levels may mean higher risk of side effects. Women taking the pill are at a higher risk of blood clots, particularly, perhaps, if they have been consuming grapefruit. Taking the pill with grapefruit may increase blood concentrations by 137%.
If suppressing our drug-clearance enzymes with grapefruit juice elevates levels of ingested estrogen, what might it be doing to our own estrogen levels? This study, associating grapefruit consumption with breast cancer, freaked out the medical community. But, subsequent studies on even larger groups of women found no evidence of a link. In fact, if anything, the Harvard Nurses’ Study found a decreased risk of the scariest breast cancer type.
So, it doesn’t look like one has to worry about grapefruit affecting our natural chemistry. But, for those prescribed unnatural chemistries, it may be a good idea to “discontinue grapefruit consumption for 72 hours before use of a drug that may interact with it.” If you don’t want to give up your grapefruit, you can ask your doctor about switching from one of the grapefruit-affected drugs, like Lipitor, to one of the citrus-proof alternatives.
Please consider volunteering to help out on the site.
- K. R. Monroe, S. P. Murphy, L. N. Kolonel, M. C. Pike. Prospective study of grapefruit intake and risk of breast cancer in postmenopausal women: The Multiethnic Cohort Study. Br. J. Cancer. 2007 97(3):440 - 445.
- E. A. Spencer, T. J. Key, P. N. Appleby, C. H. van Gils, A. Olsen, A. Tjonneland, F. Clavel-Chapelon, M.-C. Boutron-Ruault, M. Touillaud, M.-J. Sánchez, S. Bingham, K. T. Khaw, N. Slimani, R. Kaaks, E. Riboli. Prospective study of the association between grapefruit intake and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC). Cancer Causes Control 2009 20(6):803 - 809.
- E. H. Kim, S. E. Hankinson, A. H. Eliassen, W. C. Willett. A prospective study of grapefruit and grapefruit juice intake and breast cancer risk. Br. J. Cancer 2008 98(1):240 - 241.
- M. C. de Oliveira, R. Sichieri, R. V. Mozzer. A low-energy-dense diet adding fruit reduces weight and energy intake in women. Appetite 2008 51(2):291 - 295.
- C. A. Dow, S. B. Going, H.-H. S. Chow, B. S. Patil, C. A. Thomson. The effects of daily consumption of grapefruit on body weight, lipids, and blood pressure in healthy, overweight adults. Metab. Clin. Exp. 2012 61(7):1026 - 1035.
- S. Gorinstein, A. Caspi, I. Libman, H. T. Lerner, D. Huang, H. Leontowicz, M. Leontowicz, Z. Tashma, E. Katrich, S. Feng, S. Trakhtenberg. Red grapefruit positively influences serum triglyceride level in patients suffering from coronary atherosclerosis: Studies in vitro and in humans. J. Agric. Food. Chem. 2006 54(5):1887 - 1892.
- L. Rodríguez-Fragoso, J. L. Martínez-Arismendi, D. Orozco-Bustos, J. Reyes-Esparza, E. Torres, S. W. Burchiel. Potential risks resulting from fruit/vegetable-drug interactions: Effects on drug-metabolizing enzymes and drug transporters. J. Food Sci. 2011 76(4):R112 - R124.
- M. J. Ratain, E. E. Cohen. The value meal: How to save $1,700 per month or more on lapatinib. J. Clin. Oncol. 2007 25(23):3397 - 3398.
- K. Fujioka, F. Greenway, J. Sheard, Y. Ying. The effects of grapefruit on weight and insulin resistance: Relationship to the metabolic syndrome. J Med Food 2006 9(1):49 - 54.
- M. J. Ratain. Flushing oral oncology drugs down the toilet. J. Clin. Oncol. 2011 29(30):3958 - 3959.
- A. M. Karch. The grapefruit challenge: The juice inhibits a crucial enzyme, with possibly fatal consequences. Am J Nurs. 2004 104(12):33 - 35.
- L. A. Grande, R. D. Mendez, R. T. Krug, E.-J. Verschuyl. Attention--grapefruit!. Lancet 2009 373(9670):1222.
- A. Weber, R. Jäger, A. Börner, G. Klinger, R. Vollanth, K. Matthey, A. Balogh. Can grapefruit juice influence ethinylestradiol bioavailability? Contraception 1996 53(1):41 - 47.
- A. L. Stump, T. Mayo, A. Blum. Management of grapefruit-drug interactions. Am Fam Physician 2006 74(4):605 - 608.
- H. J. Silver, M. S. Dietrich, K. D. Niswender. Effects of grapefruit, grapefruit juice and water preloads on energy balance, weight loss, body composition, and cardiometabolic risk in free-living obese adults. Nutr Metab (Lond) 2011 8(1):8.
- U. Fuhr, K. Klittich, A. H. Staib. Inhibitory effect of grapefruit juice and its bitter principal, naringenin, on CYP1A2 dependent metabolism of caffeine in man. Br J Clin Pharmacol 1993 35(4):431 - 436.
- P. M. Owira, J. A. Ojewole. The grapefruit: An old wine in a new glass? Metabolic and cardiovascular perspectives. Cardiovasc J Afr. 2010 21(5):280-285.
- E. Cunningham, W. Marcason. Is it possible to burn calories by eating grapefruit or vinegar? J Am Diet Assoc. 2001 101(10):1198.
- J. E. Flood-Obbagy, B. J. Rolls. The effect of fruit in different forms on energy intake and satiety at a meal. Appetite. 2009 52(2):416-422.
Images thanks to Dan Zen, Mtsofan, gálibo and sewm via flickr and Lokal_Profil via Wikimedia
- agua
- ahorro de costos
- alimentación a base de vegetales
- bebidas
- cafeína
- cáncer
- cáncer de mama
- cítricos
- coágulos de sangre
- colesterol
- colesterol LDL
- efecto placebo
- efectos secundarios
- enfermedad cardiaca
- estatinas
- Estudio de Salud de Enfermeras de Harvard
- flexitarianos
- fruta
- grasa
- grasa abdominal
- grasa corporal
- hipertensión
- Lipitor
- manzanas
- medicamentos
- mitos de la nutrición
- mortalidad
- obesidad
- peras
- pérdida de peso
- píldoras anticonceptivas
- presión arterial
- presión arterial alta
- salud de la mujer
- salud mamaria
- toronja
- triglicéridos
- veganos
- vegetarianos
- verduras
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
If you have people eat half a grapefruit three times a day before each meal for a couple months, they may lose about two pounds. But, that’s no more than if they ate three apples or pears a day. In this study, the grapefruit-eaters not only saw their weight go down, but their waist got slimmer, and their body fat melted away. If, however, you repeat the experiment, and instead ask people to drink a half-cup of water before each meal, you get the same result. So, this belief that grapefruit has some special fat-burning quality appears to be just a “long-held myth.”
Here’s the latest, showing grapefruit consumers had a drop in weight, significant drop in cholesterol, significant drop in blood pressure. “Conclusion: This study suggests that consumption of grapefruit daily for 6 weeks does not significantly decrease body weight, cholesterol, or blood pressure.” What?! That made me do a little double take. But again, it’s because the grapefruit just didn’t do any better than placebo.
Other studies have found a legitimate cholesterol-lowering benefit—especially eating red, as opposed to white, grapefruits—and, even a little dip in triglycerides. This was one grapefruit a day for 30 days. But, as you can see, though, they went from one life-threatening cholesterol level to another life-threatening cholesterol level. To prevent heart disease, you really have to get down to a total cholesterol of around 150—the average cholesterol of those eating diets composed exclusively of plant foods, not just grapefruits.
Even though grapefruits alone don’t do much, the researchers suggest that people might be more likely to stick with them than cholesterol-lowering drugs, noting that most people with heart disease stop taking their statin drugs within a couple years, because of the adverse side effects, whereas grapefruit alone don’t have any side effects. But, ironically, combine grapefruits and drugs together, and you can make drug side effects even worse.
Now, hopefully, if you eat lots of fruits and veggies, you won’t need a lot of drugs. But, certain phytochemicals in plants can affect the metabolism of drugs in the body, and grapefruit is the poster child—described as “a pharmacologist’s nightmare.” Natural phytochemicals in grapefruit suppress the enzymes that help clear more than half of commonly prescribed drugs, and so, less drug clearance means higher drug levels in the body. Now, this may be good, if you want a better caffeine buzz from your morning coffee, or your doctor wants to help you save thousands of dollars boosting the effects of expensive drugs, instead of just peeing them down the toilet.
But, higher drug levels may mean higher risk of side effects. Women taking the pill are at a higher risk of blood clots, particularly, perhaps, if they have been consuming grapefruit. Taking the pill with grapefruit may increase blood concentrations by 137%.
If suppressing our drug-clearance enzymes with grapefruit juice elevates levels of ingested estrogen, what might it be doing to our own estrogen levels? This study, associating grapefruit consumption with breast cancer, freaked out the medical community. But, subsequent studies on even larger groups of women found no evidence of a link. In fact, if anything, the Harvard Nurses’ Study found a decreased risk of the scariest breast cancer type.
So, it doesn’t look like one has to worry about grapefruit affecting our natural chemistry. But, for those prescribed unnatural chemistries, it may be a good idea to “discontinue grapefruit consumption for 72 hours before use of a drug that may interact with it.” If you don’t want to give up your grapefruit, you can ask your doctor about switching from one of the grapefruit-affected drugs, like Lipitor, to one of the citrus-proof alternatives.
Please consider volunteering to help out on the site.
- K. R. Monroe, S. P. Murphy, L. N. Kolonel, M. C. Pike. Prospective study of grapefruit intake and risk of breast cancer in postmenopausal women: The Multiethnic Cohort Study. Br. J. Cancer. 2007 97(3):440 - 445.
- E. A. Spencer, T. J. Key, P. N. Appleby, C. H. van Gils, A. Olsen, A. Tjonneland, F. Clavel-Chapelon, M.-C. Boutron-Ruault, M. Touillaud, M.-J. Sánchez, S. Bingham, K. T. Khaw, N. Slimani, R. Kaaks, E. Riboli. Prospective study of the association between grapefruit intake and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC). Cancer Causes Control 2009 20(6):803 - 809.
- E. H. Kim, S. E. Hankinson, A. H. Eliassen, W. C. Willett. A prospective study of grapefruit and grapefruit juice intake and breast cancer risk. Br. J. Cancer 2008 98(1):240 - 241.
- M. C. de Oliveira, R. Sichieri, R. V. Mozzer. A low-energy-dense diet adding fruit reduces weight and energy intake in women. Appetite 2008 51(2):291 - 295.
- C. A. Dow, S. B. Going, H.-H. S. Chow, B. S. Patil, C. A. Thomson. The effects of daily consumption of grapefruit on body weight, lipids, and blood pressure in healthy, overweight adults. Metab. Clin. Exp. 2012 61(7):1026 - 1035.
- S. Gorinstein, A. Caspi, I. Libman, H. T. Lerner, D. Huang, H. Leontowicz, M. Leontowicz, Z. Tashma, E. Katrich, S. Feng, S. Trakhtenberg. Red grapefruit positively influences serum triglyceride level in patients suffering from coronary atherosclerosis: Studies in vitro and in humans. J. Agric. Food. Chem. 2006 54(5):1887 - 1892.
- L. Rodríguez-Fragoso, J. L. Martínez-Arismendi, D. Orozco-Bustos, J. Reyes-Esparza, E. Torres, S. W. Burchiel. Potential risks resulting from fruit/vegetable-drug interactions: Effects on drug-metabolizing enzymes and drug transporters. J. Food Sci. 2011 76(4):R112 - R124.
- M. J. Ratain, E. E. Cohen. The value meal: How to save $1,700 per month or more on lapatinib. J. Clin. Oncol. 2007 25(23):3397 - 3398.
- K. Fujioka, F. Greenway, J. Sheard, Y. Ying. The effects of grapefruit on weight and insulin resistance: Relationship to the metabolic syndrome. J Med Food 2006 9(1):49 - 54.
- M. J. Ratain. Flushing oral oncology drugs down the toilet. J. Clin. Oncol. 2011 29(30):3958 - 3959.
- A. M. Karch. The grapefruit challenge: The juice inhibits a crucial enzyme, with possibly fatal consequences. Am J Nurs. 2004 104(12):33 - 35.
- L. A. Grande, R. D. Mendez, R. T. Krug, E.-J. Verschuyl. Attention--grapefruit!. Lancet 2009 373(9670):1222.
- A. Weber, R. Jäger, A. Börner, G. Klinger, R. Vollanth, K. Matthey, A. Balogh. Can grapefruit juice influence ethinylestradiol bioavailability? Contraception 1996 53(1):41 - 47.
- A. L. Stump, T. Mayo, A. Blum. Management of grapefruit-drug interactions. Am Fam Physician 2006 74(4):605 - 608.
- H. J. Silver, M. S. Dietrich, K. D. Niswender. Effects of grapefruit, grapefruit juice and water preloads on energy balance, weight loss, body composition, and cardiometabolic risk in free-living obese adults. Nutr Metab (Lond) 2011 8(1):8.
- U. Fuhr, K. Klittich, A. H. Staib. Inhibitory effect of grapefruit juice and its bitter principal, naringenin, on CYP1A2 dependent metabolism of caffeine in man. Br J Clin Pharmacol 1993 35(4):431 - 436.
- P. M. Owira, J. A. Ojewole. The grapefruit: An old wine in a new glass? Metabolic and cardiovascular perspectives. Cardiovasc J Afr. 2010 21(5):280-285.
- E. Cunningham, W. Marcason. Is it possible to burn calories by eating grapefruit or vinegar? J Am Diet Assoc. 2001 101(10):1198.
- J. E. Flood-Obbagy, B. J. Rolls. The effect of fruit in different forms on energy intake and satiety at a meal. Appetite. 2009 52(2):416-422.
Images thanks to Dan Zen, Mtsofan, gálibo and sewm via flickr and Lokal_Profil via Wikimedia
- agua
- ahorro de costos
- alimentación a base de vegetales
- bebidas
- cafeína
- cáncer
- cáncer de mama
- cítricos
- coágulos de sangre
- colesterol
- colesterol LDL
- efecto placebo
- efectos secundarios
- enfermedad cardiaca
- estatinas
- Estudio de Salud de Enfermeras de Harvard
- flexitarianos
- fruta
- grasa
- grasa abdominal
- grasa corporal
- hipertensión
- Lipitor
- manzanas
- medicamentos
- mitos de la nutrición
- mortalidad
- obesidad
- peras
- pérdida de peso
- píldoras anticonceptivas
- presión arterial
- presión arterial alta
- salud de la mujer
- salud mamaria
- toronja
- triglicéridos
- veganos
- vegetarianos
- verduras
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Tell Your Doctor if You Eat Grapefruit
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URLNota del Doctor
Another benefit of not taking drugs? You don’t have to worry about grapefruit consumption! See Say No to Drugs by Saying Yes to More Plants.
We don’t want to take cholesterol-lowering drugs unless we need to. To get cholesterol down naturally, see:
Another video on the risks associated with taking estrogens: Plant-Based Bioidentical Hormones.
Other videos on citrus include:
- Reducing Muscle Fatigue with Citrus
- Keeping your Hands Warm with Citrus
- Which Fruit Fights Cancer Better?
- Anti-Angiogenesis: Cutting Off Tumor Supply Lines
- Boosting Heart Nerve Control
For more context, check out my associated blog post: How Grapefruit Affects Prescription Drugs.
Échale un vistazo a la página de información sobre los recursos traducidos.