Effect of short-term high dietary calcium intake on 24-h energy expenditure

[EvelynS]

Effect of short-term high dietary calcium intake on 24-h energy expenditure, fat oxidation, and fecal fat excretion.

Jacobsen R, Lorenzen JK, Toubro S, Krog-Mikkelsen I, Astrup A.
Department of Human Nutrition, Centre for Advanced Food Studies, The Royal Veterinary and Agricultural University, DK-1958 Frederiksberg C, Denmark.
Int J Obes Relat Metab Disord. 2005 Jan 18


BACKGROUND:: Observational studies have shown an inverse association between dietary calcium intake and body weight, and a causal relation is likely. However, the underlying mechanisms are not understood.

OBJECTIVE:: We examined whether high and low calcium intakes from mainly low-fat dairy products, in diets high or normal in protein content, have effects on 24-h energy expenditure (EE) and substrate oxidation, fecal energy and fat excretion, and concentrations of substrates and hormones involved in energy metabolism and appetite.

DESIGN:: In all, 10 subjects participated in a randomized crossover study of three isocaloric 1-week diets with: low calcium and normal protein (LC/NP: 500 mg calcium, 15% of energy (E%) from protein), high calcium and normal protein (HC/NP: 1800 mg calcium, 15E% protein), and high calcium and high protein (HC/HP: 1800 mg calcium, 23E% protein).

RESULTS:: The calcium intake had no effect on 24-h EE or fat oxidation, but fecal fat excretion increased approximately 2.5-fold during the HC/NP diet compared with the LC/NP and the HC/HP diets (14.2 vs 6.0 and 5.9 g/day; P<0.05). The HC/NP diet also increased fecal energy excretion as compared with the LC/NP and the HC/HP diets (1045 vs 684 and 668 kJ/day; P<0.05). There were no effects on blood cholesterol, free fatty acids, triacylglycerol, insulin, leptin, or thyroid hormones.

CONCLUSIONS:: A short-term increase in dietary calcium intake, together with a normal protein intake, increased fecal fat and energy excretion by approximately 350 kJ/day. This observation may contribute to explain why a high-calcium diet produces weight loss, and it suggests that an interaction with dietary protein level may be important.

[Nancy LC]

fecal energy

There's a term you don't hear every day.

[doreen T]

... increased fecal fat and energy excretion by approximately 350 kJ/day.
Just for reference ... 1 kilocalorie (commonly just called "calorie") = 4.186 kilojoules.

So 350kj = 83.6 kcal


Doreen

[littlejohn]

Nancy :lol:

Ok, did that say that over 24 hours it is good to eat calcium rich foods to enhance weight loss?

[Wyvrn]

So more calcium decreases absorption of dietary fat. For those of us who eat more fat on purpose, because it's good for us, this is NOT desirable.

Wyv

[mcsblues]

... but its not something "we" have to worry about because "we" wouldn't consider 23% protein as "high protein" - which according to this very small, very short term study negated the effect of high calcium.

[Wyvrn]

There's a term you don't hear every day.

But just think of the possibilities! People who do this could sell their poop back to the power company!

Wyv

[ceberezin]

Or Willie Nelson could run his van on it.

[Nancy LC]

I wonder how much fecal energy it would take to light Las Vegas?

[Wyvrn]

Maybe The Matrix could happen. But instead of leeching body heat, or brainwaves (or whatever it was), it would run on methane. So, what'll it be... the little purple pill... or the steak?

Wyv

[Duparc]

So I increase the fat in my diet for health purposes then increase the calcium intake to clear the fat from my system? No way!

[bluesmoke]

Seems to me that a great many of these studies are powered by male cow fecal energy. Nyah Levi

[nobimbo]

Calcium mechanism for weight loss gets clinical support


25/02/2005 - Calcium could reduce body weight by binding fat in the intestine and increasing its excretion from the body, say Danish researchers, who have provided the first clinical evidence to support a mechanism for the weight loss effect of dairy produce.

Several epidemiological studies in recent years have showed an inverse relationship between calcium intake and body weight. In 2002, a US team reported that a high calcium diet resulted in greater weight and fat loss in obese adults on a low-calorie diet than in those on a low calcium diet.
Researchers have suggested some possible mechanisms for this effect but there has been little evidence so far to support the observational findings.

The new study, published in the March issue of the International Journal of Obesity (vol 29, no 3, pp 292-301), shows that fat excreted in the faeces increased 2.5-fold in people on a high calcium diet compared with when they lowered their calcium intake.

Lead author Professor Arne Astrup at the Royal Veterinary and Agricultural University in Denmark says that this mechanism could be enough to explain a 4kg drop in weight over a year.

“I had this hypothesis that calcium could bind fat in the GI tract and had to find out if it could affect weight through faecal fat excretion. But it surprised us that it was so much,” he told NutraIngredients.com.

A short-term boost in dietary calcium increased faecal fat and energy excretion by around 350 kJ per day.

“This is a very solid finding and seen across all of the subjects,” added Professor Astrup.

The researchers set up a trial that tightly controlled the diets and energy expenditure of 10 healthy, moderately overweight volunteers. The randomized crossover study tested three diets with different calcium and protein levels, mainly from low-fat dairy products.

These were low calcium (500mg) and normal protein (making up 15 per cent of energy), high calcium (1800mg) and normal protein and high calcium and high protein (23 per cent of energy).

Calcium intake had no effect on 24-hour energy excretion or fat oxidation, ruling out one previously suggested mechanism that the mineral could affect the mineral’s role in fat metabolism by influencing fat's oxidation.

However faecal fat excretion came to 14.2g per day for the high calcium, normal protein diet, compared to 6g for the low calcium diet and 5.9g for the low calcium, high protein diet.

The high calcium diet also increased faecal energy excretion as compared with the other diets.

There were no effects on blood cholesterol, free fatty acids, triacylglycerol, insulin, leptin, or thyroid hormones.

The findings are important because this is the first human intervention study to support calcium’s fat-binding mechanism through consumption of dairy products.

“The mechanism by which calcium increases fat excretion is probably an interaction between calcium and fatty acids, resulting in the formation of insoluble calcium fatty acid soaps and hence in reduced fat absorption,” write the authors.

Professor Astrup noted: “We now have a very good explanation for this effect on weight but there may be others. There could be an effect of calcium on appetite but we wouldn’t have seen it as we controlled energy intake among the subjects.”

Astrup’s team has begun working on further human trials to test the mechanisms of calcium on weight.

The study does not explain the differences seen previously between dairy products and a lower effect from supplements.

http://www.nutraingredients.com/news/news-ng.asp?n=58328-calcium-mechanism-for

[Dodger]

I'm not sure that reduced fat absorption is good. Along with the fats goes the fat soluble vitamins.

It is interesting that the calcium used in this study was low-fat dairy. If I consume milk, I definetely get increased increased faecal fat and energy excretion. Of course it has nothing to do with the calcium, just the lactose in the milk. This study could well be showing that most people have some amount of lactose intolerance since calcium pills don't show the same result.