Quote:
Originally Posted by JohnP
Naringenin is in grapefruits. In mice, this has been shown to reduce insulin. We are not mice. This has not been replicated in humans.
In a human study, grapefruit before a meal in diabetics showed a slight increase in insulin sensativity that grapefruit juice did not cause. Why? Grapefruits themselves have lots of fiber.
Grapefruits do have a lot of nutrients and fiber without many calories so in that sense I'd agree they are a good addition to anyone's diet assuming there are no bad drug interactions but they don't speed up your metabolism.
Hope this helps.
By the way - I love it when I am wrong. It means I learned something new. So by all means, please point out when you think I am wrong.
You have an excellent approach and attitude! I love to learn, too.
There have been several medical studies now linking grapefruit with weight loss. Here for instance is an abstract from the Endocrinology Division at Scripps Clinic in La Jolla, California. It points out that regardless of consumption of fibre of grapefruit, insulin resistance improves.
Summary: Human Study Confirms Grapefruit Promotes Weight Loss
A study published in the March 2006 issue of the
Journal of Medicinal Food supports the long-held belief that grapefruit is useful in the battle of the bulge. Dr. Ken Fujioka from Scripps Clinic in San Diego conducted a 12-week study of 100 obese men and women and found that consuming one-half grapefruit before meals resulted in an average weight loss of 3.6 pounds with some participants losing up to 10 pounds. Individuals who ate the grapefruit had significantly lower levels of insulin in their blood, which the researchers speculated resulted in the weight loss. Insulin promotes hunger, so having lower levels of insulin in the blood helps dieters control hunger. The researchers further speculated that a natural plant compound in grapefruit, not the fiber content, was responsible for the weight loss since those who consumed grapefruit juice also lost weight despite the lack of fiber.
The effects of grapefruit on weight and insulin resistance: relationship to the metabolic syndrome.
Fujioka K, Greenway F, Sheard J, Ying Y.
Source: Division of Endocrinology, Department of Nutrition and Metabolic Research, Scripps Clinic, La Jolla, California 92130, USA.
[email protected]
Abstract
To study the effects of grapefruit and grapefruit products on body weight and metabolic syndrome, 91 obese patients were randomized to either placebo capsules and 7 ounces (207 mL) of apple juice, grapefruit capsules with 7 ounces (207 mL) of apple juice, 8 ounces (237 mL) of grapefruit juice with placebo capsule, or half of a fresh grapefruit with a placebo capsule three times a day before each meal. Metabolic syndrome parameters were measured at the beginning and end of 12 weeks. After 12 weeks, the fresh grapefruit group had lost 1.6 kg, the grapefruit juice group had lost 1.5 kg, the grapefruit capsule group had lost 1.1 kg, and the placebo group had lost 0.3 kg. The fresh grapefruit group lost significantly more weight than the placebo group (P < .05).
A secondary analysis of those with the metabolic syndrome in the four treatment groups demonstrated a significantly greater weight loss in the grapefruit, grapefruit capsule, and grapefruit juice groups compared with placebo (P < .02). There was also a significant reduction in 2-hour post-glucose insulin level in the grapefruit group compared with placebo. Half of a fresh grapefruit eaten before meals was associated with significant weight loss. In metabolic syndrome patients the effect was also seen with grapefruit products. Insulin resistance was improved with fresh grapefruit. Although the mechanism of this weight loss is unknown it would appear reasonable to include grapefruit in a weight reduction diet.
http://www.ncbi.nlm.nih.gov/pubmed/16579728
