Weight Cycling vs. Ad Lib and CRON

[Guest guest]

Hi folks:

Here is a (to me at least) astonishing study of the effects of

different eating behaviours on mammary cancer in mice susceptible to

the disease.

It finds, of course, that CRON reduces the incidence of mammary

cancers compared with ad lib. But it also seems to find that mice

whose caloric intake (and body weight) was cycled three weeks high,

three weeks low, had much less cancer than CRON animals consuming the

same amount of food on average as the cycled mice, but fed the same

amount each day.

===========================

***** Does anyone have additional information from other studies on

the effects on cancer incidence of cycling of energy intake? *****

===========================

Here are some excerpts from the abstract:

" ........ The consequence of intermittent caloric

restriction/refeeding resulting in weight-cycling was evaluated using

an oncogene-induced MT (mammary tumor) mouse model. ...........

" Ad libitum-fed mice were fed AIN-93M diet.

" Beginning at 10 weeks of age, weight-cycled mice were fed an AIN-93

modified diet (2-fold increase in protein, fat, vitamin, and mineral

contents) at 50% of ad libitum for 3-week intervals, followed by 3-

week intervals of ad libitum feeding using AIN-93M diet.

" Pair-fed mice were fed a 2:1 mixture of AIN-93M:AIN-93 modified

diets to match the caloric intake of weight-cycled mice for each 6-

week age-matched caloric restriction/refeeding interval. .......

" Ad libitum-fed mice had a 77% MT incidence versus 3% for weight-

cycled and 44% for pair-fed mice. MTs were detected earlier for ad

libitum-fed mice, 64.1 weeks versus 73.5 weeks for pair-fed mice. The

only MT in one weight-cycled mouse was excised at necropsy (80 weeks

of age) and weighed only 0.063 g. Average MT weight for ad libitum-

fed mice was 1.034 g and for pair-fed mice was 0.667 g.

" Intervals of caloric restriction/refeeding resulting in weight-

cycling were protective against MT development in this mouse model. "

PMID: 12223427

The full text is available free.

Rodney.