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“Do you eat a lot of fat?” the doctor asks a new patient. “Oh, no, I really try not to,” is the most common response.
“Wrong answer,” says David Perlmutter, MD, board certified neurologist and author of Grain Brain: The Surprising Truth about Wheat, Carbs, and Sugar-Your Brain’s Silent Killers. The emphasis on avoiding fat, says Perlmutter, has increased the amount of carbohydrates in our diet to such an extent that they’re driving soaring rates of Alzheimer’s disease, while depleting us of fats that are building blocks for healthy brain function. But with the right diet, Alzheimer’s is, as he puts it, “absolutely a preventable disease.” »
This flies in the teeth of common wisdom, as does Perlmutter’s assessment of the cause of Alzheimer’s. In conventional medical thinking, brain plaques are believed to cause the disease, or at least be the chief contributing factor.
Not so, says Perlmutter. “Alzheimer’s is inflammation of the brain,” he says. “The plaques are a response that the brain is mounting against the inflammation, not the other way around.” The latest imaging studies show that half of people with high plaque levels are completely normal, he adds, and drugs that target plaque make patients more demented, not better.
In short, Perlmutter has discovered that today’s conventional perspective on Alzheimer’s disease, the most common form of dementia, is fraught with unsound principles that block effective prevention. He has also found a nutritional solution.
The Genetic Key
We can’t change our genes. However, says Perlmutter, “We have the profound ability to modify our genetic expression, based upon our lifestyle choices.” And genetic expression is what determines whether or not we get Alzheimer’s or other diseases.
Our food influences which genes are turned on or off. The combination of carb overload, lack of the right fat, and often gluten, turns on genes that raise risk for Alzheimer’s.
Carbs and Sugar-Eating too many carbs and too much sugar for too long leads to chronically high blood sugar levels. Imaging studies show that chronic high blood sugar, at levels that are medically considered “normal,” contribute to shrinkage of the brain.
More specifically, an A1c test measures blood sugar during the previous three months. A reading below 5.7 is considered normal, 5.7-6.4 is prediabetic, and 6.5 or higher is diagnosed as diabetes, which doubles risk for Alzheimer’s. But risk for the disease, says Perlmutter, begins to increase when A1c is higher than 5.2.
Fats-It’s well known that omega-3 fats from fish, and fat in olive oil, are anti-inflammatory and good for every aspect of our health, but saturated fats are misunderstood, says Perlmutter. Studies show that saturated fats (even butter) neither raise nor lower inflammation but are necessary building blocks for the brain. There is one caveat: Fat from conventionally raised animals is toxic, because they’re fed pro-inflammatory corn and pesticide-laden feed, which isn’t their natural diet.
Good sources of saturated fat include meat, eggs, and dairy products from animals that are grass-fed, free-range, and raised without the use of hormones, antibiotics, or pesticides. Coconut oil and avocados are other good sources of beneficial fats.
Gluten-Sensitivity to gluten can trigger dementia, says Perlmutter. And it’s under-diagnosed-so much so that he recommends everyone get checked with a comprehensive test such as that from Cyrex Laboratories (cyrexlabs.com). Many commonly used tests aren’t sensitive enough to detect intolerance. But gluten poses a much bigger problem.
“Even in small amounts, in everybody, not just those who are so-called gluten sensitive, it actually disrupts the junctions in the gut,” he says. This leads to a leaky gut, which triggers autoimmune reactions and inflammation in the whole body, including the brain.
Although the degree of reaction to gluten varies from one person to another, says Perlmutter, it’s an ingredient that is best avoided by everyone.
The Right Diet
At first glance, the diet seems pretty simple. Skip over gluten-filled grains, starchy vegetables, and sugar, and eat anything that’s left, making sure to choose only organic, grass-fed meat and dairy products, fish that isn’t toxic, and organic versions of everything else.
However, putting this theory into practice is another story, because most of the food that surrounds us is high in starchy carbohydrates or sugar, or doesn’t fit the bill in other ways. Even “healthy” foods can come with pitfalls. For example, gluten-free foods can be high in starch. Fruit juices, although nutritious, are high in sugar. Meats and dairy products that are both organic and grass-fed can be difficult to find.
But the more you do find, the better off you’ll be, and the underlying principles Perlmutter recommends are quite realistic to put into practice. For example:
- Eat a piece of fruit instead of drinking fruit juice, but no more than one piece per day.
- Instead of milk in coffee, use (organic, grass-fed) heavy cream, because milk contains sugar in the form of lactose, but cream contains much less.
- Eat lots of aboveground vegetables, which are less starchy than their underground cousins. You can even juice them, if you like.
- Eat eggs for breakfast, without the toast. Add goat cheese, avocado, or both, and any vegetables you like.
- Use coconut oil for cooking.
- Plan meals that contain a variety of vegetables-grilled, steamed, lightly sautéed, or raw-along with wild salmon or other low-mercury fish, or grass-fed, organic meat or poultry.
- Enjoy extra virgin olive oil and a variety of vinegars or citrus juices on salads.
- Choose sauces without sugar. Butter-based ones are fine as long as the butter is grass-fed and organic.
- Go wild with seasonings.
In addition, don’t forget aerobic exercise. Any movement that raises your heart rate, done regularly, can cut your risk for Alzheimer’s in half. “You can change, by your lifestyle choices, your genetic destiny,” says Perlmutter, “and that’s so empowering.”
Along with the right diet, Perlmutter recommends these supplements:
DHA: 1,000 mg daily. Ideally, take DHA derived from fish oil, either as a DHA supplement or in a fish oil product that contains a combination of DHA and EPA, the key omega-3 fatty acids. If you’re vegan, look for DHA derived from algae-it can be found in some protein powders and oils, in addition to pills. Regardless, be sure to get a daily dose of 1,000 mg of DHA.
Resveratrol: 100 mg daily.
Turmeric: 200 mg daily (about a pinch of powdered turmeric).
Probiotics: A daily dose that contains at least 10 billion active cultures from at least 10 different strains, including Lactobacillus acidophilus and Bifidobacterium.
Coconut oil: 1 tsp. daily.
Alpha-lipoic acid: 300 mg daily.
Vitamin D: 5,000 IU daily, or get your blood levels tested to determine your personal needs.