-IBIS-1.7.6-
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food
Grapefruit
Nutrition

nutrition

definition

grapefruit:

Ayurvedic: Kapha

Chinese:
» qualities: cold, sweet, sour
» actions: aids digestion, strengthens Stomach, moves Qi
» uses: alcoholism, weak digestion, stomach fullness, dry cough

naturopathic:
» qualities: alkaline-forming food
» actions: lowers blood pressure, protects arteries, lowers the risk of cancer, stimulates appetite, dissolves catarrh in small amounts (large amounts may cause boils, irritated nerves, diarrhea)
» uses:
fruit: insomnia (take before bed), liver problems, hypertension, arteriosclerosis, kidney stones, gallstones
juice: fevers and constipation
rind and pith: cardiovascular health: atherosclerosis, hypertension, cerebrovascular accident; common cold, scurvy; schizophrenia; rheumatism, arthritis; hemorrhoids, varicose veins, bruising; asthma, food allergies, peptic and duodenal ulcers, hayfever
» contraindications:
• general: colitis, peptic ulcers, hyperchlorhydria
• drug interactions:
» Nifedipine: Grapefruit juice increases the bioavailability of nifedipine (Procardia, Adalat) by 8-69%, possibly through bioflavonoid interfernece with cytochrome P450 (Cantoni, et al., 1982; 307; 1079)
» Lovastatin: Grapefruit juice can greatly increase serum concentrations of lovastatin and its active metabolite, lovastatin acid, probably by preventing CYP3A4-mediated first-pass metabolism in the small intestine. The concomitant use of grapefruit juice with lovastatin and simvastatin should be avoided, or the dose of these 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors should be reduced accordingly. (Kantola T, et al. Clin Pharmacol Ther 1998 Mar;63(4):397-402.
» Cyclosporine: Grapefruit juice increases blood concentrations of some dihydropyridine calcium-channel blockers, which are metabolised by the P450 enzymes that also metabolise cyclosporine. Thus concurrent administration of grapefruit juice with cyclosporine will delay the absorption of the cyclosporine and increase the drug exposure of cyclosporine without changing peak concentration. Therefore, lower doses of cyclosporine are required to achieve the desired levels in the body when adminstered in conjunction with grapefruit juice. Thus grapefruit juice may provide a non-toxic and inexpensive alternative to drugs that are used to reduce cyclosporin dose.
(Yee GC, et al. Lancet 1995 Apr 15;345(8955):955-956; Min DI, et al. Transplantation 1996 Jul 15;62(1):123-125.)


biochemical: high in pectin; potassium; bioflavonoids (pulp) and vitamin C
» form: raw white grapefruit
» portion: 0.5 of medium
» calories (kcal): 39
» weight (g): 118
» water (%): 90.7
» protein (g): 0.8
» fat (g): 0.1
» carbohydrates (g): 9.9
» unsaturated fatty acid (g): 0.1
» saturated fatty acid (g): 0
» calories from fat (%): 2.3
» cholesterol (mg): 0
» dietary fiber (g):
» vitamin A (RE): 1
» vitamin A (IU): 12
» vitamin B1 (mg): 0.04
» vitamin B2 (mg): 0.02
» vitamin B3 (mg): 0.3
» vitamin B6 (mg): 0.04
» vitamin B12 (mcg): 0
» vitamin C (mg): 39
» vitamin E (IU): 0.26
» folic acid (mcg): 12
» pantothenic acid (mg): 0.33
» sodium (mg): 0
» potassium (mg): 175
» calcium (mg): 14
» phosphorus (mg): 9
» magnesium (mg): 11
» iron (mg): 0.07
» zinc (mg): 0.08
» copper (mg): 0.059
» manganese (mg): 0.015



footnotes

Agriculture Handbook #8

Airola, p. 291

Carper, p. 213

Jensen, pp. 153-155

Johari, p. 111

Kantola T, Kivisto KT, Neuvonen PJ. Grapefruit juice greatly increases serum concentrations of lovastatin and lovastatin acid. Clin Pharmacol Ther 1998 Mar;63(4):397-402.
Abstract: BACKGROUND: Grapefruit juice increases the bioavailability of several drugs known to be metabolized by CYP3A4. We wanted to investigate a possible interaction of grapefruit juice with lovastatin, a cholesterol-lowering agent that is partially metabolized by CY P3A4. METHODS: An open, randomized, two-phase crossover study with an interval of 2 weeks between the phases was carried out. Ten healthy volunteers took either 200 ml double-strength grapefruit juice or water orally three times a day for 2 days. On day 3, each subject ingested 80 mg lovastatin with either 200 ml grapefruit juice or water, and an additional dose of 200 ml was ingested 1/2 and 1 1/2 hours after lovastatin intake. Serum concentrations of lovastatin and lovastatin acid were measured up to 12 hours. RESULTS: Grapefruit juice greatly increased the serum concentrations of both lovastatin and lovastatin acid. The mean peak serum concentration (Cmax) of lovastatin was increased about 12-fold (range, 5.2-fold to 19.7-fold; p < 0.001) and the area under the concentration-time curve [AUC(0-12)] was increased 15-fold (range, 5.7-fold to 26.3-fold; p < 0.001) by grapefruit juice. The mean Cmax and AUC(0-12) of lovastatin acid were increased about fourfold (range, 1.8-fold to 11.5-fold; p < 0.001) and fivefold (range, 2.4-fold to 23.3-fold; p < 0.001) by grapefruit juice, respectively. The half-lives of lovastatin and lovastatin acid remained unchanged. CONCLUSIONS: Grapefruit juice can greatly increase serum concentrations of lovastatin and its active metabolite, lovastatin acid, probably by preventing CYP3A4-mediated first-pass metabolism in the small intestine. The concomitant use of grapefruit juice with lovastatin and simvastatin should be avoided, or the dose of these 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors should be reduced accordingly.

Lu, p. 66

Min DI, Ku YM, Perry PJ, Ukah FO, Ashton K, Martin MF, Hunsicker LG. Effect of grapefruit juice on cyclosporine pharmacokinetics in renal transplant patients. Transplantation 1996 Jul 15;62(1):123-125.
Abstract: This study investigated the effect of grapefruit juice on cyclosporine A (CsA) bioavailability in 10 renal transplant patients. Under CsA steady state conditions, patients were randomly administered their usual dose of CsA with either 8 ounces of grapefruit juice or 8 ounces of water. Using a crossover design, a 12-hr pharmacokinetic study was then conducted. Grapefruit juice increased the area under the concentration versus time curve (4218+/-1497 ng x hr/ml [grapefruit juice] vs. 3415+/-1288 ng x hr/ml [water], P=0.029) and 12-hr trough (244+/-214 ng x ml [grapefruit juice] vs. 132+/-56 ng x ml [water], P=0.09), but it did not change peak concentration (734+/-290 ng x ml [grapefruit juice] vs. 708+/-305 ng x ml [water], P=0.76). In addition, grapefruit juice delayed the time to peak concentration compared with water (5.4+/-3.0 hr [grapefruit juice] vs. 2.8+/-0.8 hr [water], P=0.025). These data suggest that concurrent administration of grapefruit juice with CsA will delay the absorption of CsA and increase the drug exposure of CsA without changing peak concentration.

Ni, p. 61

Yee GC, Stanley DL, Pessa LJ, Dalla Costa T, Beltz SE, Ruiz J, Lowenthal DT. Effect of grapefruit juice on blood cyclosporin concentration. Lancet 1995 Apr 15;345(8955):955-956.
Abstract: Grapefruit juice increases blood concentrations of some dihydropyridine calcium-channel blockers, which are metabolised by the P450 enzymes that also metabolise cyclosporin. We evaluated, in a randomised cross-over study, the effect of grapefruit juice on blood cyclosporin concentrations in 14 healthy adults. Each subject was given oral cyclosporin 300 mg with 250 mL grapefruit juice, orange juice, or water. Area-under-the-curve (AUC) was significantly higher with grapefruit juice than with water or orange juice (means 7057, 4871, and 4932 ng h/mL, respectively; p < 0.0001). Thus grapefruit juice may provide a non-toxic and inexpensive alternative to drugs that are used to reduce cyclosporin dose.