Monday, January 21, 2008

Prof Yudkin on ascorbate

Top of page 76, 1972 hardback copy of Pure, White and Deadly. Prof Yudkin is talking about mistakes in interpreting data when attributing effect to cause:

"Many older people who suffer from a variety of diseases, gradually develop a degree of heart failure, and one of the effects is swollen legs due to dropsy (oedema). This can be relieved if large amounts of vitamin C are taken, for the vitamin acts as a diuretic and increases the loss of fluid through the kidneys. Though this cures the symptoms of heart failure, the condition was clearly not due to a deficiency of vitamin C."

These have got to be perhaps three of the most intriguing sentences which I have ever read. I have great respect for Prof Yudkin, but some bits of this paragraph are completely wrong. I am fully aware that 5000mg of sodium ascorbate, taken by mouth, produces no discernible diuresis. During periods of self experimentation I have taken 20,000mg by mouth on at least 4 occasions during a single day. Although an occasionally spectacular laxative effect can be produced, and a positive urine test for glucose (due to the urinary ascorbate), frank diuresis has never been a notable effect.

So I look at Prof Yudkin's observation with interest. It is innocently made as an illustration, so I see absolutely no reason to think it is untrue. I think his explanation is incorrect. I'm not an ascorbate megadoser, Optimal Diet and its derivatives shouldn't need that. But I'm fascinated by this snippet, and what it might mean about ascorbate and heart failure in a carbohydrate eater.

Makes you think.



Anonymous said...

Do you own any of the Homo Optimus boos by Dr K...just asking because I love to read and would like to learn more about his perespectives about the optimal nutrition...but is a little complicated to order them in just checking if is worth it.
By the way, I was talking (via e-mail) to a person that has a website
and he advocates much lower levels of carbs and consequently higher levels of protein...but my point of discussion was actually the heavy cream and he doesn't recommend it because of the lactose content and regarding the "beneficial" bacteria from yogurt or fermented products he says they die in the stomach...
Any thoughts regarding this and your experiences...
and what do you think about his approac to nutrition (he says ketosis is actually healthy and zero carb is OK)...regarding that why do you try to stay out of ketosis.
Thanks and I hope I am not bothering.
Take care

Peter said...

I have both Homo Optimus and Optimal Nutrition. ON is a very simple book of recipes, types of illnesses, tips about coping on ON in social circumsatnces. It's occasioanlly inconsistent but generally a good basic guide. HO is a very, very strange book. It has far more on specific diseases but also goes in to considerable depth on Kwansiewski's views on politics, religion, more religion (some very strange ideas there), the roll of food in control of population behavior, history of Dr K's initial experiments using lab rats, himself and his family plus a great deal more........ More recipes too. A wild read, but very strange. I just wonder how much of it he's correct on..........


Anonymous said...

Thanks Peter...a question, why do you try to stay out of ketosis?

Peter said...

This got stuck in comments somewhere, here's the general idea.

There are four answers to this I think.

First is that, certainly in the short term, ketosis elevates blood cortisol and I'm not comfortable that this is good. Second is that Dr K is usually correct, goodness knows how come, he just is... Third is that I have no need for weight loss so any possible enhancement of weight loss from ketosis would just mean I had to eat more calories. Finally, if I provide enough glucose and a small (non ketonuric) level of ketones for my brain, then I can run my muscles on pure FFA and chylomicrons. No need for the liver to make ketones, take the fat straight from the food to the muscles. Elegant, efficient.

Having said that I really cannot keep fully out of ketosis on 50g carbs per day. I don't stress about intermittent ketosis. Just as well I guess...


Anonymous said...

The body makes ketones on any diet, esp a high-fat diet like JK's. Also ketotic diet mainly prevents weight gain, according to Michael Eades. A person won't lose excessive weight. unless they are literally starving. The "metabolic advantage" if any is small, for actual weight los. There seems to be an advantage for weight maintenance. You can eat more food, on a high-fat diet, without gaining weight.

Puddleg said...

I have almost always been underweight on a high-carb diet; I gained 3-4 Kg on an intermittent ketosis diet, plateuing at a level that's still rather lean but feels and looks much better.

Puddleg said...

After a daily dose of 5 mg/kg for three days a significant
increase in urinary volume was observed in 30 children (10 active
rheumatic, 10 convalescent rheumatic patients and 10 controls)
(Abbasy, 1937). This diuretic effect was confirmed in another study on
nine patients with heart failure, given 300 mg of ascorbic acid daily
(Evans, 1938).

Doses up to 6000 mg of ascorbic acid were given to 29 infants,
93 children of preschool and school age, and 20 adults for more than
1400 days. With the higher doses, toxic manifestations were observed
in five adults and four infants. The signs and symptoms in adults were
nausea, vomiting, diarrhoea, flushing of the face, headache, fatigue
and disturbed sleep. The main toxic reactions in the infants were skin
rashes (Widenbauer, 1936).

Studies in man indicate that ascorbic acid has a diuretic effect
at 5 mg/kg bw in children and adults and glycosuria was observed with
doses of 30-100 mg/kg.

M said...

"Red meat and vit.C
Cooked red meat should not be a problem, unless some of your problem bacteria are starved for iron -- see the adjacent post by Cristian.

That would suggest that some zinc supplements might be helpful.

I mentioned vitamin C as an anti-oxidant. I think that some people are also deficient in vit.C and have incipient scurvy symptoms with weakened connective tissue. Vit.C gets depleted under condition of chronic inflammation with associated production of ROS. Even lots of sun exposure can deplete vit.C. Under those conditions it may take more vit.C supplement than a gram a day. That can be checked by gradually increasing the vit.C supplement until the excess spills over into the gut and causes diarrhea.

So, if you can't take more than a gram a day without diarrhea, that could mean that you aren't consuming extra vit.C due to extra oxidative stress."