Friday, November 13, 2009

Atkins-style low carb, high protein dieters 'more likely to suffer depression'

The Atkins diet has often evoked a huge and and apparently irrational hostility -- so we must be cautious about results such as these. The anti-meat brigade, among others, certainly hate its success. Note that even the authors below note a social rather than a physiological cause for the effects they observed. It is also not totally obvious why being on a restricted diet improves mood. I would have thought that such a diet would make you grumpy

People who try to lose weight using an Atkins-style low carb, high protein diet are more likely to suffer depression, a study suggests. Slimmers on a low-calorie and low-fat diet saw their mood improve more than counterparts on a low-carbohydrate regime with the same amount of calories, found researchers.

Two groups of overweight or obese patients were studied over the course of a year in Australia and the findings are published in the latest issue of Archives of Internal Medicine. It was found that, although both groups lost an average of more than two stone, those patients on a low-fat diet experienced a lasting improvement in mood compared with the low-carb group.

The authors of the study said that the results serve as a warning against the growing trend for low-carb, high-protein plans like the Atkins Diet. "While recent clinical studies have shown that low-carbohydrate diets can be an effective alternative dietary approach for weight loss, their long-term effects on psychological function, including mood and cognition, have been poorly studied," wrote the authors.

Possible explanations for the results of the study include the social difficulties associated with sticking to a low-carb plan, which prescribes a different regime from the typical pasta and bread-filled Western diet. The structure of such diets could also affect mood, said the authors.

The effects of protein and fat on the levels of serotonin the 'happiness chemical' could also offer an explanation.

The authors added that further studies would be required to see how other cognitive functions are affected by different dietary regimes.


Many breast cancers do not need treatment

HUNDREDS of women every year are having treatments for breast cancer, including surgery and chemotherapy, that are unnecessary because nearly one-third of cancers detected by screening tests are not dangerous. Australian researchers have proven for the first time that breast cancer screening is responsible for substantial "overdiagnosis" of the disease -- the detection of cancers that are too slow-growing to cause a problem in the woman's lifetime but are still treated as if they pose an immediate threat.

The University of Sydney experts found the overdiagnosis rate was between 30 and 42 per cent -- meaning between 23 and 29 per cent of women aged 50-69 are having cancer treatments they do not need.

While previous studies have estimated overdiagnosis rates as high as 52 per cent from breast cancer screening, the new study is the first to rule out other known causes of breast cancer as being an alternative explanation for the higher detection rate, which has doubled since screening began. Obesity, use of hormone replacement therapy and childlessness all increase the risk of breast cancer, and have been rising over the same period.

But the researchers, who included world-renowned cancer expert Bruce Armstrong, have shown these other factors cannot explain the higher cancer rate among screened women, which they said could "only be explained by overdiagnosis".

Figures published by the Australian Institute of Health and Welfare last month show that 6398 women aged 50-69 were diagnosed with breast cancer in 2006. If the higher 29 per cent overdiagnosis figure were correct, it would suggest about 1855 women each year are receiving unnecessary treatments, including mastectomies and radiation.

Co-author Alex Barratt, associate professor of epidemiology at the University of Sydney, said the study "conclusively shows that . . . it's a phenomenon caused by screening". "We need better screening tests that either don't pick up these very slow-growing cancers in the first place, or triage tests that are able to tell the difference once they are detected."

Australia's breast screening program has been under increased pressure from the numbers of younger women seeking scans following the cases of celebrities such as Kylie Minogue. In September, an evaluation report of the BreastScreen Australia program proposed restricting access to free screening for younger women.

Some cancer experts have reacted cautiously to the findings, warning that the relevance for individual women was limited because doctors could not tell which cancers detected by mammography could be safely ignored.

Cancer Council Australia chief executive Ian Olver said the study's results were "a guesstimate" and screening had slashed the death rate from breast cancer by about 35 per cent among women aged 50-69 since mammograms for healthy women were introduced in 1990.

Associate Professor Barratt said any woman who detected a symptom such as a lump, breast changes or discharge should seek medical advice straightaway, as the non-dangerous cancers did not produce these signs.



Anonymous said...

The study about moods caused by the Atkins diet makes sense if you factor in the idea that a depressed person moves around less, has a lower energy level and is more capable of taking abuse without retaliating.

Those are all perfectly natural adaptations to making it possible for people to survive cramped and uncomfortable conditions during winter when the portions of carbs in a diet would naturally go down and be replaced by protein from hunting.

It seem that the people studying diet never seem to consider the natural responses of the body to environmental conditions, for most of the time humans have been on the earth winter has been a time of weight loss as diet changed to a winter time diet.

We understand why bears need to fatten themselves up but don't ever consider why we tend to do so ourselves.

The problem with the study is not what they found but what conclusions they drew from it.

dearieme said...

"Australian researchers have proven for the first time ...": except that a friend worked on a research project nearly 30 years ago which found the same thing.