Tuesday, October 31, 2006

Now Alzheimer's Disease

There is a laboratory mouse strain which has been genetically engineered to develop Alzheimer's Disease. Not nice for the mouse, but very useful for research purposes. If you have a look at this abstract, it suggests that limiting calorie intake completely protects against Alzheimer's in this strain of mouse. So why does Alzheimer's still progress in humans, even when weight maintenance becomes very difficult due to the effects of the disease?

Well, the abstract is somewhat disingenuous. It is spectacularly silent about the type of calorie restriction used. Luckily the full paper is available as a pdf at the click of a link. Be warned though, this paper is about as readable as a telephone directory, in the dark, but not as well written. You have to read the abstract, the introduction, the materials and methods until finally you get to the results section. Then you find the best kept secret so far. It's on line three of the results.

Carbohydrate restriction.

OK, yes these animals were calorie restricted, but the ONLY calories removed were carbohydrate.

The discussion actually uses the C word quite a lot. That is, it mentions carbohydrate restriction rather than calorie restriction. But the final paragraph, the sum it all up paragraph, the "this is what we found" paragraph, drops right back to calorie restriction.

Can you imagine the outcry if this group had come up with the headline "Atkins type diet provides 100% protection against Alzheimer's disease in highly susceptible mouse model"? You would actually have heard the "pop" as their funding evaporated. Anyway, it was only mice.

What about humans? No one has done the study yet, though one is planned by the group that did the Parkinson's work I mentioned yesterday. What has already been done is the flip side. That is, increasing the carbohydrate intake of nursing home patients with Alzheimer's disease. This was done to try to limit their weight loss. Adding extra carbohydrate resulted in "increased carbohydrate preference, poorer memory and increased aberrant motor behavior".

And it made them fatter too.

Peter

5 comments:

Neonomide said...

Hi,

A new study showed that Saturated Fats actually were linked to Alzheimer's:

http://www.abc.net.au/science/articles/2009/09/08/2679589.htm


I'd love to see your thoughts on this.

Peter said...

Hi Neonomide,

It's a pay per view paper so it's impossible to find out how much sugar there was in their high fat diet. Genuine high fat diets are usually described in the abstract as ketogenic and the papers are usually pro saturated fat. This one is anti, so will be sucrose based.

If saturated fats caused Alzheimers you would hardly expect to ameliorate it with a ketogenic diet! Which you can do...

Peter

kathy said...

'Increased dinner intake, attributable to intervention foods, was achieved in 20 of 32 of participants who completed the study and was associated with increased carbohydrate preference, poorer memory, and increased aberrant motor behavior.'

I don't believe the poorer memory, etc., RESULTED from the increased carbs. The study was about increasing food intake. Increasing carbs did the trick in this case. No more, no less was accomplished by this study.

It was not a study about the effect of carbs on motor skills of Alzhiemer's patients.

Peter said...

Hi Kathy,

Well that's fine by me. The observation in the study abstract does say "associated", ie there was no control group.

A few ketones from MCTs do the opposite, in terms of brain function.

Most of the people I've corresponded with prefer better brain function to a fatter waistline...

Peter

Cave Chic said...

I would imagine that the negative saturated fat study was skewed in some way to make it look like they are linked to Alzheimer's increase. After all, as stated, if the diseases goes away so does the funding.