Foods That Contain Soy Is Linked To Higher Rates Of Senility
Soy is linked to higher rates of senility.
If you have started eating tofu burgers instead of hamburgers because you think soy is healthier – you may be in for a surprise. New research suggests eating tofu may make your brain age faster, leading to severe problems with memory and learning in later years.
Even if you never eat tofu
A custard-like food made from pureed soybeans – you’re still not in the clear. Soy or soybean oil is in everything from salad dressings, mayonnaise, and margarine to breakfast cereals and energy bars, making it the most widely used oil.
About 60 percent of all processed foods contain soy protein. And since it is added to cattle and other livestock feed, you may consume it indirectly just by eating your usual steak or hamburger.
Researchers in Hawaii concluded that soy might contribute to brain aging after examining the diets of more than 8,000 Japanese-American men for over 30 years. They found those who ate two or more servings of tofu a week were much more likely to become senile or forgetful as they grew older compared with men who ate little or no tofu.
The more tofu the subjects ate, the more learning and memory problems they suffered in later life. Loss of mental function occurred in 4 percent of the men who ate the least amount of tofu compared with 19 percent of the men who ate the most excellent tofu.
These are shocking results for a food touted for its health benefits and recently given FDA approval to make health claims on package labels.
Dr. Lon White, the lead researcher of the Hawaiian study, suggests the study’s findings should make people think twice about the amount of soy they eat. “What we have here is a scary idea that may turn out to be dead wrong,” he says. “Or it could turn out to be the first uncovering of an important health-negative effect of a food that we believe may have a lot of good going for it.”
White’s study included subjects ranging from 46 to 65 years old. The men were asked whether they ate certain foods associated with a traditional Japanese diet or an American diet. They were interviewed about their dietary habits again in the early 1970s and were tested for cognitive function – including attention, concentration, memory, language skills, and judgment – in the early 1990s when they were 79 to 93 years old. They were also given a brain scan at that time.
The results were disturbing. Out of 26 foods studied, only tofu was significantly related to brain function. Men who had a high intake of tofu not only scored lower on tests of mental ability but their brains were more likely to show signs of advanced age and shrinkage.
Their test scores were typical of a person four years older. Although the study was done on men, researchers also interviewed and tested 502 wives of the men in the stuffy – and came up with similar findings.
Studies About Soy Benefits
The study has created a stir because it contradicts previous research that found soy to be beneficial. Earlier studies have shown soy may fight cancer and heart disease, prevent osteoporosis, and relieve menopause symptoms. Researchers credit estrogen-like molecules called isoflavones for soy’s apparent disease-fighting properties. But those same substances could have adverse effects on the body as well, Dr White notes. He says people need to understand that isoflavones are complex chemicals that act like drugs and change the body’s chemistry.
“The great things they (consumers) have been hearing about soy foods in recent years have little to do with nutrients – carbohydrates, proteins, fats, minerals, vitamins,” he says. “All that hype is related to the idea that soy contains other kinds of molecules that act like medicines … they alter the way our body chemistry works.”
Soy Estrogen Myth ?
The isoflavones in soy are a type of phytoestrogen or plant estrogen, which mimics the estrogen produced naturally in your body. Brain cells have receptors that link up with estrogen to help maintain brain function, and White believes phytoestrogens may compete with the body’s natural estrogens for this receptor.
Many think soy’s isoflavones interfere with enzymes and amino acids in the brain. One of soy’s main isoflavones, genistein, limits the enzyme tyrosine kinase in the hippocampus – the brain’s memory center. By interfering with this enzyme activity, genistein blocks a process called “long-term potentiation” that is central to learning and memory.
Dr Gillespie Study About Soy
Dr. Gillespie, the author of The Menopause Diet, says overeating soy could result in other problems as well. She has found that consuming 40 milligrams (mg) of isoflavones a day can slow down thyroid function, resulting in hypothyroidism. Most isoflavone supplements come in a 40mg dose, and just 6 ounces of tofu or 2 cups of soy milk would supply the same amount. Also, because isoflavones act like estrogen, some studies suggest that postmenopausal women who eat a lot of soy may increase their breast cancer risk.
And scientists have questioned the potential effects of soy on infants as well. One study found infants who drank soy formula received six to “times as many phytoestrogens as the amount known to have hormonal effects in adults.
Some think this could lead to early puberty, which is associated with a greater risk for breast cancer and ovarian cysts.
This leads to the question of whether soy’s good aspects outweigh the negative ones.
“Whatever good effects come with the gift (soy), will also come at some cost, “White says. “We do not know yet just what those costs are, just as we don’t know the full and honest extent of their health benefits yet. We’re flying blind, and my data are very, very disturbing.”
The Hawaiian study was a long-term, well-designed, controlled study, but it was just one study. The results are strong enough to make you sit up and take notice, but only more research can confirm them.
If you eat soy
If you eat soy, you may want to err on the side of caution. Be sure you know the number of soy isoflavones you consume each day, avoid soy supplements and soy-enriched consume foods (like some nutritional bars) until more research is done.