Dairy foods + CR better?

[Guest guest]

Hi All,

This paper has much CR studies in it:

Am J Clin Nutr. 2004 May;79(5):907S-912S.

Role of calcium and dairy products in energy partitioning and weight

management.

Zemel MB.

Dietary calcium plays a pivotal role in the regulation of energy

metabolism

because high-calcium diets attenuate adipocyte lipid accretion and

weight gain

during the overconsumption of an energy-dense diet and increase

lipolysis and

preserve thermogenesis during caloric restriction, which thereby

markedly

accelerates weight loss. Intracellular Ca(2+) plays a key regulatory

role in

adipocyte lipid metabolism and triacylglycerol storage; increased

intracellular

Ca(2+) results in the stimulation of lipogenic gene expression and

lipogenesis

and the suppression of lipolysis, which results in increased lipid

filling and

increased adiposity. Moreover, the increased calcitriol produced in

response to

low-calcium diets stimulates adipocyte Ca(2+) influx and,

consequently, promotes

adiposity, whereas higher-calcium diets inhibit lipogenesis, inhibit

diet-induced obesity in mice, and promote lipolysis, lipid oxidation,

and

thermogenesis. Notably, dairy sources of calcium markedly attenuate

weight and

fat gain and accelerate fat loss to a greater degree than do

supplemental

sources of calcium. This augmented effect of dairy products relative

to

supplemental calcium is likely due to additional bioactive compounds,

including

the angiotensin-converting enzyme inhibitors and the rich

concentration of

branched-chain amino acids in whey, which act synergistically with

calcium to

attenuate adiposity. These concepts are confirmed by epidemiologic

data and

recent clinical trials, which indicate that diets that include > or

=3 daily

servings of dairy products result in significant reductions in

adipose tissue

mass in obese humans in the absence of caloric restriction and

markedly

accelerate weight and body fat loss secondary to caloric restriction

compared

with diets low in dairy products. These data indicate an important

role for

dairy products in both the prevention and treatment of obesity.

PMID: 15113738 [PubMed - in process]

.... For example, although there is a well-established

relation between salt intake and blood pressure con-trol,

the inability of most patients to comply with highly sodium-restricted

diets presents a nearly overwhelming barrier to the

success of these diets, not unlike the general inability of individ-

ual

persons to adhere to energy-restricted weight-control diets

for extended periods of time. In contrast, the DASH (Dietary

Approaches to Stop Hypertension) diet presents, instead, the

positive approach of increasing fruit, vegetable, and dairy intakes

to lower blood pressure, and numerous studies now attest to the

relative success of these less-restrictive dairy-rich or DASH-based

diets in controlling blood pressure (1–3). Notably, recent

evidence now indicates that these same diets play a significant

role in the partitioning of dietary energy and may be helpful in the

prevention and management of obesity.

.... When the same diets were fed in combination with

modest energy restriction to diet-induced, obese, transgenic

mice, the low-calcium diet markedly inhibited adipose tissue

lipolysis, accelerated lipogenesis, and impeded weight and fat

loss secondary to energy restriction. In contrast, the high-calcium

diets markedly accelerated weight and fat loss at identical levels

of energy restriction, whereas dairy sources of calcium further

augmented this effect by 50–70% compared with calcium car-bonate

(5, 23–26).

Wealso evaluated the effects of calcium and dairy products on

the partitioning of dietary energy during refeeding after weight

loss in this model. Obesity was induced by feeding a low-calcium

obesigenic diet for 6 wk, after which all animals were placed on

an energy-restricted high-calcium diet for an additional 6 wk to

induce weight loss. The animals were then provided ad libitum

access to low-calcium, high-calcium, or high dairy diets for an

additional 6 wk. Although the animals fed the low-calcium diet

rapidly regained all of the weight and fat that had been lost,

refeeding of the high-calcium diets prevented the suppression of

adipose tissue lipolysis and fat oxidation that otherwise accom-panies

postdieting repletion and markedly up-regulated indexes

of skeletal muscle fat oxidation (27). Consequently, although the

animals that were refed low-calcium diets rapidly regained all of

the weight and fat that had been lost, the animals fed high-calcium

diets showed a shift in energy partitioning and a 50–

85% reduction in weight and fat gain. Moreover, dairy products

exerted markedly greater effects than did supplemental calcium

on fat oxidation and fat gain (27). These data are supported by

both observational data and clinical trials, as described in the next

sections.

...We conducted several clinical trials that evaluated the modu-

lating

effects of calcium and dairy products on adiposity in per-sons

consuming energy-restricted or eucaloric diets (43–45). In

the initial trial (43), 32 obese adults were maintained on balanced

calorie-deficit diets (500 kcal/d deficit) and then randomly as-signed

to a control diet (0 –1 servings/d and 400–500 mg Ca/d

supplemented with placebo), a high-calcium diet (control diet

supplemented with 800 mg Ca/d), or a diet high in dairy products

(3–4 servings of milk, yogurt, or cheese daily; total calcium

intake of 1200–1300 mg/d). Control subjects lost 6.4% of their

body weight over the 24-wk study, and this loss was increased by

26% with the high-calcium diet and by 70% (to 10.9%) with the

diet high in dairy products (P 0.01). Fat loss (measured by

dual-energy X-ray absorptiometry) followed a similar trend; the

high-calcium diet and the diet high in dairy products augmented

the fat loss that occurred with the low-calcium diet by 38% and

64%, respectively (P 0.01). An unexpected finding was a

marked change in the distribution of body fat loss (43). Fat loss

from the trunk region represented 19%of the total fat lost with the

low-calcium diet, and this loss increased to 50% of the fat lost

with the high-calcium diet and to 66% of the fat lost with the diet

high in dairy products (P 0.001). These findings show that an

increase in dietary calcium from suboptimal to adequate amounts

can enhance the efficacy of an energy-restricted diet in achieving

weight and fat losses. Furthermore, these effects are markedly

greater when dairy foods rather than calcium supplements are

consumed (43).

We confirmed these findings in a follow-up clinical trial in 34

obese subjects who consumed a diet supplemented with 3 serv-ings

of yogurt compared with a placebo control group who con-sumed

a balanced calorie-deficit diet (500 kcal/d deficit) for 12

wk (44). Dietary macronutrient and fiber intakes were held con-stant

at the US average, and the control group maintained a

calcium intake of 400–500 mg/d, whereas the yogurt group

achieved an intake of 1100 mgCa/d. Both groups lost weight, but

the yogurt group lost 61% more fat and 81% more trunk fat than

did the control group (P 0.001). Similar to the first clinical trial,

the fraction of fat lost from the trunk was markedly higher with

the yogurt diet than with the control diet (60.0% compared with

26.4%). Moreover, there was a significant 31% reduction in the

loss of lean tissue mass during energy restriction in the yogurt

group compared with the control group. No adverse effects on

any serum lipid fraction were observed in either of these trials,

and an improvement in insulin sensitivity, glucose tolerance, and

blood pressure were observed in the dairy product groups in both

trials.

We also recently showed that increases in dairy intakes result

in improvements in body composition in the absence of energy

deficits. Isocaloric substitution of 3 daily servings of dairy prod-

ucts

into the diets of obese African American adults maintained

on eucaloric diets for 6 mo resulted in a 5.4% reduction in total

body fat and a 4.6% decrease in trunk fat (P 0.01 for both) in

the absence of any change in body weight. The control group

maintained on a low-calcium, low-dairy diet with an identical

macronutrient composition showed no significant changes in

total body fat or trunk fat (45). Accordingly, it appears that the

use of dairy products to attain an optimal calcium intake during

energy restriction results in a marked augmentation of weight

loss, a loss of total fat and trunk fat, and a relative preservation

of

lean body tissue compared with the same degree of energy re-striction

with a low-dairy diet. Further incorporation of dairy

products in the absence of energy restriction appears to result in

a repartitioning of dietary energy from adipose tissue to lean

body mass, resulting in a net reduction in fat mass (43–45).

...weight and fat loss in energy-restricted aP2-agouti transgenic

mice (26). However, the combination of the calcium and ACE

inhibitor was markedly less potent than was either milk or whey

in reducing body fat; moreover, milk and whey both substantially

preserved skeletal muscle mass during energy restriction,

whereas calcium and the combination of calcium and ACE in-hibitor

had no effect. Thus, whey components—including cal-cium,

BCAAs, ACE inhibitors, and possibly other whey com-ponents—

appear to exert a synergistic effect on adiposity and

energy partitioning.

CONCLUSIONS

Anantiobesity effect of dietary calcium and dairy foods is now

evident from animal studies, observational and population stud-ies,

and clinical trials. Although there is a strong theoretical

framework in place to explain the effects of dietary calcium on

energy metabolism, the precise mechanisms whereby dairy prod-ucts

exert substantially greater effects than do equivalent

amounts of calcium are not yet clear. However, these additional

effects are likely to be mediated, in part, by whey-derived bio-active

compounds, including ACE inhibitors, and by the high

concentration of BCAAs in whey protein. These data provide the

framework for the development of an effective weight manage-ment

strategy—based on the use of dairy products in a DASH-based

diet—for the prevention of overweight and obesity and for

the control of energy balance.....

15. Shi H, DiRienzo D, Zemel MB. Effects of dietary calcium on

adipocyte

lipid metabolism and body weight regulation in energy-restricted aP2-

agouti transgenic mice. FASEB J 2001;15:291–3.

21. Shi H, Norman AW, Okamura WH, Sen A, Zemel MB. 1(-25-

dihydroxyvitamin D3 inhibits uncoupling protein 2 expression in human

adipocytes. FASEB J 2002;16:1808 –10.

22. Sun X, Zemel MB. Role of uncoupling protein 2 (UCP2) expression

and

1 ,25-Dihydroxyvitamin D3 in modulating adipocyte apoptosis. Obes

Res 2003;11:A37(abstr).

23. Zemel MB, Sun X, Geng X. Effects of a calcium-fortified breakfast

cereal on adiposity in a transgenic mouse model of obesity. FASEB J

2001;15:A598(abstr).

24. Zemel MB, Geng X. Dietary calcium and yogurt accelerate body fat

loss

secondary to caloric restriction in aP2-agouti transgenic mice. Obes

Res

2001;9:146S(abstract).

25. Zemel MB, K. Interaction between calcium, dairy and dietary

macronutrients in modulating body composition in obese mice. FASEB

J 2002;16:A369(abstr).

26. Causey KR, Zemel MB. Dairy augmentation of the anti-obesity

effect of

Ca in aP2- agouti transgenic mice. FASEB J 2003;A746(abstr).

27. Sun X, Zemel MB. Calcium and dairy inhibition of weight and fat

regain

during ad libitum feeding following energy restriction in aP2-agouti

transgenic mice. FASEB J 2003;17:A746(abstr).

43. Zemel MB, W, Milstead, et al. Dietary calcium and dairy

products accelerate weight and fat loss during energy restriction in

obese

adults. Obes Res (in press).

44. Zemel MB, Nocton AM, s JD, et al. Dairy (yogurt) augments

fat

loss and reduces central adiposity during energy restriction in obese

subjects. FASEB J 2003;A1088(abstr).

45. Zemel B, Nocton AM, s J, et al. Increasing dairy calcium

intake

reduces adiposity in obese African-American adults. Circulation 2002;

106(suppl):II-610(abstr).

Cheers, Alan Pater, PhD; 4849 Swanson St., Port Alberni, BC, V9Y 6M7;

phone: 250

724-0596; email: old542000@...