With 5.4 million Americans already living with Alzheimer’s disease, one in five suffering from mild cognitive impairment (MCI), and the 2012 failure of several targeted pharmaceutical drug trials, many brain health experts are now focusing on food as a critical defense against dementia.
“Over the past several years, there have been many well-designed scientific studies that show you are what you eat when it comes to preserving and improving memory,” says Dr. Richard Isaacson, associate professor of neurology at the University of Miami Miller School of Medicine and author of The Alzheimer’s Diet.
In recent years, studies published in the Journal of the American Medical Association and Archives of Neurology have shown that people on a Mediterranean-type diet—high in antioxidant-rich fruits and vegetables, whole grains and fatty fish, and low in refined carbohydrates and saturated fats—tend to fend off cognitive decline longer and be less prone to developing full-blown Alzheimer’s. Several small, but promising clinical trials further suggest that even people that have already begun to suffer memory loss may be able to slow or mildly reverse it via nutritional changes. Here’s how.
Switch to slow-burning carbs: Mounting evidence indicates that the constant insulin spikes from eating refined carbohydrates like white bread or sugar-sweetened sodas can eventually impair the metabolization of sugar (similar to Type 2 diabetes), effecting blood vessel damage and hastened aging. A high-carb diet has also been linked to increased levels of beta-amyloid, a fibrous plaque that harms brain cells.
A 2012 Mayo Clinic study of 1,230 people ages 70 to 89 found that those that ate the most carbs had four times the risk of developing MCI than those that ate the least. Inversely, a small study by University of Cincinnati researchers found that when adults with MCI were placed on a low-carb diet for six weeks, their memory improved.
Isaacson recommends switching to slow-burning, low-glycemic index carbohydrates, which keep blood sugars at bay. Substitute whole grains and vegetables for white rice, pastas and sugary fruits. Water down juices or forego them altogether.
Choose fats wisely: Arizona neurologist Dr. Marwan Sabbagh, co-author of The Alzheimer’s Prevention Cookbook, points to numerous studies suggesting a link between saturated fat in butter, cooking oil, cheese and processed meats and increased risk of Alzheimer’s. “In animals, it seems to promote amyloid production in the brain,” he says.
In contrast, those that eat more fatty fish such as herring, halibut and wild-caught salmon that are rich in the anti-inflammatory omega-3 fatty acid DHA, are at lower risk. Sabbagh notes that DHA, when it’s a steady part of the diet, plays a critical role in forming the protective “skin of the brain” known as the bilipid membrane, and may possibly offset production of plaque in the brain, thus slowing its progression during the earliest stages of dementia. Aim for three weekly servings of fatty fish. Vegetarians can alternatively consider supplementing meals with 1,000 to 1,500 milligrams daily of DHA, says Isaacson.
Eat more berries and kale: In general, antioxidant-rich fruits (especially berries) and vegetables are major preventers of oxidative stress—the cell-damaging process that occurs naturally in the brain as we age.
One recent study published in the Annals of Neurology found that women eating high amounts of blueberries and strawberries were able to stave off cognitive decline 2.5 years longer than those that did not. Rich in antioxidant flavonoids, blueberries may even have what Sabbagh terms, “specific anti-Alzheimer’s and cell-saving properties.”
Isaacson highlights the helpfulness of kale and green leafy vegetables, which are loaded with antioxidants and brain-boosting B vitamins. One recent University of Oxford study in the UK of 266 elderly people with mild cognitive impairment found that those taking a blend of vitamins B12, B6 and folate daily showed significantly less brain shrinkage over a two-year period than those that did not.
Spice up: Sabbagh notes that India has some of the lowest worldwide rates of Alzheimer’s. One possible reason is the population’s love of curry. Curcumin, a compound found in the curry-flavoring spice turmeric, is another potent antioxidant and anti-inflammatory.
He recommends sprinkling one teaspoon of curcumin on our food every day and cooking with antioxidant-rich cloves, oregano, thyme, rosemary and cinnamon. A 2011 Israeli study at Tel Aviv University found that plaque deposits dissolved and memory and learning behaviors improved in animals given a potent cinnamon extract.
Begin a brain-healthy diet as early as possible. “Brain changes can start 25 years before the onset of dementia symptoms,” says Sabbagh. “It’s the end result of a long process, so don’t wait. Start your prevention plan today.”