Phytoestrogens in soy

[SPE]

All three...

Why don't you just take a little of all three? Then you cover your bases.

 

[usufruct]

What I find confusing is that if saturated fat causes high cholesterol then why do certain groups of people such as the Samburu (Masaai tribe) who for a period of over 20 years ingest nearly 400 grams of saturated fat a day yet when measured for cholesterol level these guys only had totals in the 150's? Where is the causality? It's not absolute. Surely other factors are involved. It's interesting when these guys leave the pastures and move to the big cities and eat a more conventional diet higher in carbs and lower in saturated fat then they start to show evidence of heart disease. I believe George Mann, former director of the Framingham study on diet and cholesterol studied these people in the 70's.

 

[usufruct]

Just to expound on what I posted earlier. This is a quote from the Cholesterol Myths:

The Masai [of Kenya] drink 'only' half a gallon of [whole] milk each day...Their parties are sheer orgies of meat; on such occasions four to ten pounds of meat [eaten] per person is not unusual, according to Professor [George] Mann [of Vanderbilt University in Nashville, TN, USA]. If the diet-heart idea were correct, coronary heart disease would be epidemic in Kenya. But Professor Mann found that the Masai do not die from heart disease - although they might die from laughter if they heard about the campaign against foods containing cholesterol and saturated fat. But this was not the only surprise. The cholesterol of the Masai tribesmen was not sky-high as Mann had expected; it was the lowest ever measured in the world, about 50% lower than the value of most Americans."

 

[mranak]

...who for a period of over 20 years ingest nearly 400 grams of saturated fat a day...

That's 3,600 calories/day just from fat. And I do assume that they also inject at least _some_ carbs and/or protein, which adds to the calories. Something seems wrong here.

Certainly, many people on low-carb diets, loaded with saturated fat, have good lipid profiles. My wife and I did the low-carb thing for two years. Her cholesterol was great, especially the Total Cholesterol:HDL ratio. But I was on the same diet and my cholesterol was above 300 and the ratio was bad. Clearly, genetics are important. My cholesterol tends to sit above 300 unless I am on a NO-fat diet or take medication.

 

[usufruct]

I got the info about the 400 grams from this website: http://www.theomnivore.com/sat-fat-chol-CHD.html. It references a journal article: Shaper, AG. Cardiovascular studies in the Samburu tribe of Northern Kenya. American Heart Journal, 63 (4); 437-442, 1962 as its source.

Here's a quote from the website:

"Another east African tribe, the Samburus, have an even higher fat intake than the Masai. Whilst they eat less meat, the Samburus tend to consume far more milk than the Masai. Samburu warriors and elders may consume between 4.5 to 7 liters of high fat milk in a single sitting. During the wet season when grass is abundant and their cattle consequently produce more milk, they will do this twice a day. This amount may drop to a "mere" 2 to 3.5 liters daily during the dry season. As a result of their copious milk intake, the slender Samburu males consume up to a whopping 400g of animal fat daily."

 

[porkhide]

follow your cattle around on foot in the african heat your whole life and see how many callories you need
a liitle different than 8 hours at the cubicle

 

[SWALE]

How about if we boil it all down to this:

Many women have found relief form their menopausal symptoms by taking soy. These symptoms are caused by a deficiency in estrogen. Therefore soy acts as estrogen. Need we say more?

 

[mranak]

I don't think it is fair to make a firm conclusion based on that logic. It certainly lends itself to a good hypothosis, however.

 

[usufruct]

Plus soy may damage fertility. Keep in mind that Asians never typically (traditionally) consumed 25 grams of soy protein a day or drank soy latte or soy milk.

http://www.cnn.com/2005/HEALTH/06/22/fertility.soya.reut/index.html


Study: Soya threat to fertility

Friday, June 24, 2005; Posted: 10:59 a.m. EDT (14:59 GMT)


Scientists found genistein could cause sperms to "burn out." What Is This? COPENHAGEN, Denmark (Reuters) -- A plant chemical found in soya, tofu and legumes could potentially damage sperm and affect male fertility, a British researcher said on Wednesday.

Professor Lynn Fraser, of King's College London has shown that genistein, which can mimic the effect of the female hormone oestrogen, affects sperm in mice.

But it seems to have an even stronger impact on human sperm.

In laboratory tests, Fraser found that small amounts of the chemical can cause human sperm to "burn out" and lose fertility.

"Human sperm proved to be even more responsive than mouse sperm to genistein," Fraser told a fertility meeting.

She added that if women eat soya and other foods high in genistein it might have a bigger impact on male fertility because the chemical is likely to affect sperm when it is in the female preparing to fertilize an egg.

"Maternal exposure to the compounds is probably more important than paternal exposure," Fraser explained.

Although it is very preliminary research, Fraser speculated that the findings could have an impact on women trying to conceive.

"On the basis of what we have seen, it might be a practical thing to do if you are in the habit of eating lots of soya-based products to restrict your diet for a short time over the window of ovulation," she told the European Society of Human Reproduction and Embryology meeting.

Professor Richard Sharpe, of Edinburgh University in Scotland, described the research as interesting and said the results were surprising.

"It could of course have human health/fertility implications as indicated by the authors," he said in a statement.

But Sharpe added that societies that traditionally eat a soya-rich diet show no signs of reduced fertility that he is aware of.

The effects on sperm in the laboratory may also not be directly related to what may happens in real life.

Dr Allan Pacey, of the University of Sheffield in England, said it is worrying if these compounds affect mature sperm.

"It's early days, but clearly if what happens in the laboratory also occurs in the woman's fallopian tube as the sperm make their way to the egg, then there would be the potential for fertilization to fail," he explained.