Dr Leibel tells us why 95 percent of dieters gain the weight back
The following is a transcript from a speech by Dr Rudy Leibel, a renown obesity researcher details the biochemical system which kicks in when there IS a weight loss, to force the individual to gain back the weight (likely why 95 to 98 percent of dieters regain the weight within 5 years, a statistic Dr Leibel quotes himself in this speech).
Dr Leibel also mentions melanin-concentrating hormone (MCH) mutations - this is the one gene which can account for 5 percent of obesity in children, Dr Leibel stated. Since the true figures on the clinically obese are about at 15 percent we can see that they have even found the gene which accounts for 33 percent of these!
Dr Leibel also comments that the heritability of obesity is 65 percent (from the twin studies which have been done) and that there are AT LEAST (if not more, he said) 30 to 40 genes involved in obesity.
From Dr Leibel's studies of formerly obese (who are keeping weight off), he observed that they are hungry all the time, are cold and other symptoms of the biochemical system kicking in to force a weight gain. When they exercise, these individuals burn 15 to 20 percent LESS calories than a normally thin person and they evidence large amounts of cortisol in the blood (the cortisol has been observed in some studies to cause weight gain in and of itself). Dr Leibel's comment was:
> "the system is set up to defend bodyfat so if you monkey with it down here, all hell breaks out and the body goes haywire!" <
Dr Leibel feels that even a small weight loss (as little as 10 lbs) can be beneficial but comments that for most people it is impossible to keep the weight off even WITH medications like Meridia (which he said posed an independent cardio-vascular risk and must be taken constantly). "Even with that," he concluded, "after a few years, the medication seems to lose its effect and the individual re-gains the weight."
So if we ARE obese individuals, what can we do? Dr Leibel states that ALL the methods to keep weight lower than the body wants, are ineffective in most people except the gastric bypass. In gastric bypass patients, studies show that some patients can keep off significant amounts of weight (average BMI under 35) but he called this invasive surgery, a "draconian" solution that posed tremendous risks to the patient in terms of malnutritional and medical issues and therefore he did not recommend it.
Leibel feels that the current research may be the most productive. Several pharmaceuticals are working on solutions which interfere with this powerful biochemical system which forces a regain of lost weight in most people.
In the meantime, he mentioned that a loss of a small amount of weight can reduce risk factors. The HAES study suggested that those risk factors were reduced NOT because of the weight loss itself but because of the lifestyle changes which had been made which had caused modest amounts of weight loss.
In the Cooper Institute studies of 20,000 men, the lean men who were physically fit showed the least risk. But the risk factor of the men who were FAT and physically fit was only 0.1 point more than the normal weight men who were physically fit (0.2 points higher than the lean physically fit men) - this is a statistically insignificant risk differential . To be significant a risk factor, the differential must be greater than 1.0 points difference.
Normal, fit men: RR = 0.83
Obese, fit men: RR = 0.90
Lean, fit men: RR = 1.0
In a Harvard Health newsletter, which favors the research of Dr Willet (who is thought to be affiliated with the Atkins corp. since his studies are listed on the Atkins site with results favorable to the Atkins plan) and Jo Ann Manson who has admitted being a consultant to a couple of pharmaceuticals which produce diet drugs, even THIS NEWSLETTER admits that, in the Cooper Institute studies, the risk factor differential between Lean-fit men, normal weight-fit men and fat-fit men was INSIGNIFICANT
> Moreover, the all-cause mortality rate of fit, overweight men wasn’t significantly different from that of the fit, lean men. Their heretical conclusion: If you’re fit, being overweight doesn’t increase mortality risk. <
They also quote another study reported on in the JAMA which found similar results:
>A study in the Journal of the American Medical Association (JAMA) in September 2004 came to a similar conclusion. For almost four years, the researchers tracked heart attacks and other “cardiovascular events” among 900 American women who had had a coronary angiogram. They found that lack of physical activity, as calculated from answers to standard questionnaires, was a better predictor of an adverse event than weight. <
HAES or Health at Every size - focusing on lifestyle changes and better food choices (which usually results in a small loss of weight which is often gained back later), seems the answer for now until such time that the powerful weight regaining biochemical system can be interrupted with a medication.
Rudy Leibel in a BBC video show on obesity
Leibel "Our bodies have built in a weight that they want to be"
In the Experiment detailed in the above show, the average weight gain in the cohort (all slim people) after eating 5000 calories a day and not exercising, was only 6-11 lbs!
After the experiment, they all easily went back to their normal weight without "doing anything".
This tended to suggest that the affinity to gain weight as well as the affinity to eat when no longer "hungry" may be genetic also.