We know more about what makes up a heart-healthy dietary pattern than we do about “brain food,” although research on nutrition and cognition is making important progress.
The word “pattern” deserves special attention. It’s important to focus on your overall eating pattern instead of thinking solely in terms of individual foods or nutrients. A diet that helps protect your heart and brain involves more than just eating an extra serving of broccoli and occasionally choosing grilled chicken instead of a cheeseburger. The most recent Dietary Guidelines for Americans (DGA) explains: “An eating pattern is more than the sum of its parts; it represents the totality of what individuals habitually eat and drink, and these dietary components act synergistically in relation to health. As a result, the eating pattern may be more predictive of overall health status and disease risk than individual foods or nutrients.”
Cardiovascular disease is high on the list of chronic diseases that a healthy dietary pattern can help prevent—and we’ve already seen how a healthy heart and vascular system can help protect your brain.
A Heart-Healthy Pattern
What does a dietary pattern that’s healthy for your heart look like? According to the Dietary Guidelines Advisory Committee report, a “healthy dietary pattern is higher in vegetables, fruits, whole grains, low- or nonfat dairy, seafood, legumes, and nuts, moderate in alcohol (among adults), lower in red and processed meats, and low in sugar-sweetened foods and drinks and refined grains.”
If you think a heart-healthy dietary pattern includes a strict limit on fat, think again. Based on updates in the science of how different fats affect health, the DGA overturned the previous 30 years of recommendations regarding dietary fat. In the last update, the DGA did not set a recommended limit on total fat consumption; instead, the focus shifted to the type of fat in your diet.
The DGA still advises limiting intake of saturated fat, found in foods such as red and processed meats, butter, and whole-fat dairy foods. (The recommendation about limiting dairy fat is now controversial, however, with some research showing little reason to avoid whole-fat dairy.)
Nutrition experts emphasize choosing more foods that contain unsaturated fat, such as vegetable oils, nuts, seeds, avocados, and fish rich in omega-3 fats. This change is in keeping with dietary patterns that have been linked with lower risks of chronic disease, such as a Mediterranean-style diet, which contains healthy amounts of unsaturated fat but is low in saturated fat.
“Brain Food”
Evidence is mounting for the idea that what you eat also can help protect your brain. Fewer studies have investigated the connection between diet and brain function than between diet and heart health, but the existing research does suggest that certain dietary patterns can make a difference in your brain’s ability to store, access, and retrieve information, formulate and execute plans, and make decisions.
One study, for example, found that diets high in anti-inflammatory foods were linked with a lower risk of cognitive decline and impairment. Diets that were higher in phytonutrient-rich fruits and vegetables, whole grains, and fiber were anti-inflammatory, while diets that were higher in saturated and trans fats were pro-inflammatory.
Going Mediterranean
In the annual diet rankings published by the U.S. News and World Report, the Mediterranean diet took top honors for the best overall diet as well as the best diet for healthy eating, and the DGA specifically recommends this dietary pattern. Many studies have found associations between a Mediterranean-style dietary pattern and better cardiovascular health.
While you’ve probably heard of the “Mediterranean diet,” you might not know what this term really means—and the name can be a bit confusing if you associate “Mediterranean” food with the fare offered at modern Italian or Greek eateries. Many American restaurants have “Westernized” traditional Mediterranean cuisine, resulting in dishes that are high in saturated fat and calories (think pizza with pepperoni and extra cheese or fettuccine Alfredo) and fewer vegetables, whole grains, and legumes.
When you think of a Mediterranean-style diet, think instead of the traditional fare consumed by the people of the Mediterranean region in countries such as Crete, Greece, and southern Italy around 1960. At that time, the rates of chronic disease in these Mediterranean countries were among the lowest in the world, and adult life expectancy was among the highest. The dietary pattern, which consisted mainly of fruits and vegetables, beans and nuts, healthy grains, fish, olive oil, small amounts of dairy, and red wine, proved to be much more likely to lead to lifelong good health than dietary patterns that contain more meat and processed foods and fewer fruits and vegetables.
Unlike fad diets that promise a quick fix but can’t be sustained over time, the Mediterranean-style diet isn’t difficult to stick to—it’s easy to integrate into an overall healthy lifestyle that can be maintained for the rest of your life.
A traditional Mediterranean-style diet is filled with a variety of delicious, satisfying foods, including olive oil, nuts, and other plant foods that are rich in healthy, unsaturated fat. Moderate alcohol intake—especially of red wine—is allowed. This dietary pattern also is notable for what it doesn’t include: highly processed foods.
What the Science Says
Numerous studies have reported that adhering to a Mediterranean-style diet is associated with a reduced risk of stroke and heart attack, lower LDL (“bad”) cholesterol levels, and less likelihood of obesity. Research also has linked brain benefits with following a Mediterranean-style eating pattern.
In one study, participants assigned to follow a Mediterranean-style diet scored better in tests of global cognition, executive function, and memory than a control group who was advised only to reduce fat intake. Another study reported that participants who included more fish and plant foods in their diets while eating less red meat and dairy were less likely to develop cognitive impairment.
Even countries in which the traditional eating patterns are very different from those of Mediterranean countries report brain benefits of adopting a Mediterranean-style diet. In a Scottish study of older adults, those who ate the most fruits, vegetables, olive oil, and other Mediterranean-style fare and the least fried food, red meat, and cheese had about half the expected rate of brain shrinkage as participants who ate traditional Scottish fare.
Another clinical trial suggests that the Mediterranean-style diet also might help protect your mental health. Researchers randomly assigned more than 100 adults with depression to receive either Mediterranean foods and fish oil supplements and take a Mediterranean cooking class every other week, or to attend social groups every other week. After three months, the Mediterranean-diet group was eating more vegetables, fruit, nuts, whole grains, and legumes, fewer unhealthy snacks, and less red meat.
Participants in the Mediterranean diet group experienced greater reductions in their depression symptoms than those attending the social groups. The improvements in diet and depressive symptoms held steady three months after the study ended.
The DASH Plan
As we saw in the previous chapter, hypertension is a primary risk factor for cardiovascular disease and stroke, and it’s also linked with an increased risk of dementia. The most effective diet for reducing hypertension—the Dietary Approaches to Stop Hypertension (DASH)—was designed specifically for that purpose more than two decades ago. DASH was developed by the National Heart, Lung and Blood Institute based on clinical studies that tested the effects of sodium and other nutrients on blood pressure.
How much can your blood pressure drop with the DASH diet? In one study, following the DASH diet produced reductions of 7.62 mmHg for systolic pressure and 4.22 mmHg for diastolic pressure.
Even if you don’t have high blood pressure, DASH is a healthy way to eat. In the decades since DASH was developed, numerous studies have linked the diet with a host of health benefits, including reduced risks of coronary heart disease, stroke, and heart failure. And the DASH diet was ranked second in the 2019 U.S. News and World Report rankings of healthy diets (the Mediterranean-style diet was ranked first).
DASH Ingredients
The DASH diet is high in fruits, vegetables, and low-fat dairy. It emphasizes whole grains, fish, poultry, and nuts and limits red meats, added sugars, and sodium. Overall, the plan is rich in phytonutrients, potassium, magnesium, calcium, and fiber. For a complete guide to the DASH diet, see https://tinyurl.com/yc2n5lfd.
There are many similarities between DASH and a Mediterranean-style diet, but there is one important difference: the amount of fat consumed. A Mediterranean-style diet is generous with unsaturated fats, whereas DASH limits fats from all sources (remember, DASH was formulated at a time when cutting consumption of all fat was strongly advised). Our Heart-Brain Diet favors the Mediterranean-style approach to fats, in recognition of dietary guidelines updated since the original DASH research was conducted.
MIND Melds Healthy Diets
We’ve seen that both the DASH eating plan and the Mediterranean-style diet have been linked to brain benefits, and a hybrid of these two dietary patterns—the “MIND” (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet—may be even better at protecting memory and thinking than either diet on its own.
The MIND diet has been associated with a slower rate of cognitive decline estimated to be equivalent to 7.5 years of younger mental age. These results were based on data from participants in the Rush Memory and Aging Project, ages 58 to 98, who were initially free of Alzheimer’s disease. Other studies have found a lower incidence of Alzheimer’s disease in people who closely adhered to the MIND diet.
Stroke and Dementia Risk
The MIND diet also might help stroke survivors ward off cognitive decline, according to 2018 research. In general, people who have had a stroke are twice as likely to develop dementia as the general population, but researchers discovered that stroke survivors whose diets most closely resembled the MIND diet had substantially slower rates of cognitive decline than those whose diets were least similar to the MIND diet.
Stroke survivors who scored high on the Mediterranean and DASH diets, however, did not have significant slowing in their cognitive decline. Researchers commented, “The Mediterranean and DASH diets have been shown to be protective against coronary artery disease and stroke, but it seems the nutrients emphasized in the MIND diet may be better suited to overall brain health and preserving cognition.” These include folate, vitamin E, omega-3 fatty acids, carotenoids, and flavonoids.
Making a MIND Diet
Why might the MIND diet be protective?
“Inflammation and oxidative stress play a large role in the development and progression of Alzheimer’s disease,” says Tammy Scott, PhD, a scientist at Tufts’ HNRCA Neuroscience and Aging Laboratory and consulting editor for this report. “The MIND diet particularly emphasizes foods such as green leafy vegetables, berries, and olive oil that are rich in antioxidants and anti-inflammatory agents that may help to protect against dementia and cognitive decline.”
Key ingredients in the MIND diet include:
- Green leafy vegetables: at least six servings per week
- Other vegetables: at least one serving per day
- Berries: at least two servings per week
- Nuts: at least five servings per week
- Olive oil as the primary cooking oil
- Whole grains: at least three servings per day
- Fish (not fried): at least once per week
- Beans: more than three meals per week
- Chicken or turkey (not fried): at least two meals per week
- Wine: one glass per day (optional)
Researchers noted that it’s as important to limit unhealthy foods as it is to eat healthy foods. The MIND diet recommends having less than one serving a week of red meat, cheese, fried or fast food, and pastries and sweets, and less than one tablespoon of butter a day.
Skip the Fads
The DASH, Mediterranean-style, and MIND diets are hardly the only plans promising heart and brain benefits. Plenty of fad diets claim to quickly and easily boost your heart health, melt off extra pounds, and even boost your memory. Most have some nuggets of good advice, but many go to extremes, and some may have potentially dangerous side effects. Do these diets have anything to offer for a healthy heart and brain?
Low-Carb Craze
Average Americans didn’t give “carbs” much thought until the Atkins “diet revolution.” Proponents of low-carbohydrate diets claim that eating fewer carbs forces your body to burn stored fat for energy. When you digest carbs, your body converts them to sugar in the form of glucose that goes into your bloodstream. Rising blood glucose levels prompt your body to produce more insulin, which transports the glucose from your blood into your cells for energy. When you restrict carb consumption, you have less glucose in your blood, so your body must use stored fat for energy instead.
But it’s important to consider the valuable nutrients found in many carbohydrate-containing foods before taking them off the menu. Going “low-carb” means restricting healthy whole grains, fruits, vegetables, legumes, milk, and yogurt. Some research suggests that eating too few carbohydrates might deny your brain the nutrients it needs to think clearly, so decreasing carbs also may decrease cognitive performance.
Just as with fat, the current thinking on carbs emphasizes the type of carbs you eat, rather than the amount. It is true that research suggests foods high in refined carbohydrates, such as white flour and added sugar, contribute to weight gain and diabetes risk. Since both of these conditions are unhealthy for your heart and brain, it’s wise to watch out for these types of carbs. Our Heart-Brain Diet emphasizes healthy, unprocessed carbohydrates that are packed with essential nutrients.
What About “Keto”? The latest weight-loss craze is the “ketogenic” or “keto” diet, which is similar to the extremely low-carbohydrate diet popularized by Atkins in the 1970s and again by the South Beach diet in the early 2000s. By sharply restricting carbohydrates, the keto diet forces the body to get energy from fat, which results in a release of ketones into the bloodstream. Like the Atkins diet, a keto diet is rich in proteins and fats and may be lacking in nutritious fruits, vegetables, and whole grains. The keto diet is very restrictive and it often causes fatigue, so most people don’t follow it for long. It also can be dangerous for people with kidney disease, and some doctors caution that strict adherence to a keto diet for longer than a few weeks can contribute to loss of muscle mass and heart damage.
Following the keto diet usually results in rapid weight loss, but many people regain some or all of the weight they lost once they stop the diet. Interestingly, a keto diet helps ease epilepsy symptoms in some children, but the mechanism of this effect in unclear, and speculation that the diet might have brain benefits for adults has not been supported by human studies.
Forget Low-Fat Eating
We’ve already mentioned the change in thinking about fats: Low-fat diets are out, and healthy fats are in. The low-fat, highly processed foods made by food manufacturers in the 1980s usually contained increased sugar, salt, and/or refined carbs to compensate for the reduction in fat. Eating these low-fat junk foods didn’t improve people’s diets; instead, they contributed to what has become an obesity epidemic.
It’s true that following a low-fat diet might mean consuming fewer calories, since fats are a concentrated form of calories—nine calories per gram, compared to four calories per gram of protein or carbohydrate. If you replace those fats with refined carbohydrates, however, you’ll quickly make up for any initial calorie reduction. Foods that contain fat provide a feeling of satiety and long-lasting fullness that makes it easier to control your appetite—an effect that you won’t get from refined carbs.
Our heart-brain diet emphasizes healthy, mono- and polyunsaturated fats from a variety of foods including nuts, vegetable oils, seeds, avocados, and cold-water fatty fish.
Low-Carb Versus Low-Fat. Studies have found that low-carb and low-fat diets work equally well for weight loss, at least in the short term. Experts advise that any diet you find easy to stick to—which is typically true of those with a simple “eat less of this” mantra—can be effective. Neither low-carb nor low-fat eating is a nutritious prescription for lifelong health, however.
While it’s true that any diet plan that is too permissive won’t help you control your weight or protect your heart and brain, it’s also true that any diet that forces you to deny yourself all of the foods you love is likely to be short-lived. The heart-brain diet incorporates both moderation and balance, so it is both effective and sustainable; it even includes desserts.
Eating Like a Caveman
Another recent fad is the “Paleo” diet, which claims to emulate the “natural” diet of humans who lived in the Paleolithic period, commonly called the “Stone Age.” Anthropologists have pointed out, however, that the actual diets of early humans were varied and opportunistic—in other words, they ate what they could find. If early humans were less prone to “diseases of affluence” such as heart disease, it’s likely because they died too young to develop such conditions. Also, some foods endorsed by Paleo promoters were not actually available to our Paleolithic forebears.
The Paleo diet emphasizes grass-fed meats, fish and seafood, fresh fruits and vegetables, eggs, nuts and seeds, and unrefined oils from nuts, seeds, olives, avocados, and coconuts. Some of these foods are healthy, but in practice, the Paleo diet gives followers an excuse to eat a lot of meat. The danger of eating large amounts of meat is the excessive saturated fat content—the leading dietary cause of unhealthy LDL cholesterol levels.
Paleo followers avoid cereal grains, legumes, most dairy products, refined vegetable oils, processed foods, sugar and other commercial sweeteners, and salt. It’s smart to cut down on sugar, salt, and processed foods, but whole grains, legumes, and dairy foods are important sources of nutrients. In particular, grains and legumes are good sources of slowly digested carbohydrates that give your body the steady supply of energy it requires.
As for sugars, there’s little evidence that the Paleo approach of choosing “natural” sweeteners, such as agave nectar, date sugar, honey, or maple syrup, rather than granulated sugar or other commercial sweeteners, has health benefits. All of these sweeteners contain roughly the same amount of calories and affect the body similarly.
Another issue is that most Paleo diets don’t set any limits for calories. In our calorie-rich modern world, failing to limit calories in any dietary regimen can lead to weight gain and obesity.
The bottom line is that the Paleo diet doesn’t accurately reflect what our cave-dwelling ancestors consumed, and it doesn’t contain the balance of carbs, proteins, and fats we need to keep the hearts and brains in our 21st-century bodies healthy. And the Paleo diet has not been endorsed by the American Diabetes Association, the American Heart Association, or any other large, reputable health organizations.
Vegetarian Options
Although vegetarian and vegan diets also have been growing in popularity, this does not make them “fad diets.” The benefits of plant-based dietary patterns have been solidly backed by science, and the latest dietary guidelines include a vegetarian diet as an example of a healthy dietary pattern. Eating vegan or vegetarian has been associated with lower risks of obesity, cardiovascular disease, and type 2 diabetes. Such diets tend to be lower in saturated fat than traditional Western diets, and they tend to provide more fiber, phytonutrients, and antioxidants.
Switching to a vegetarian diet doesn’t guarantee weight loss or heart-brain health, however. You still need to make smart food choices. Replacing meat with highly processed foods, such as white pasta and bread, snack chips, protein bars, and sweets, may cause you to gain weight, and it won’t lead to any health benefits.
Aim to eat whole foods as often as possible, including plenty of vegetables, fruits, legumes, and whole grains, and limit processed foods that contain sodium, added sugar, saturated fat, and refined grains, such as white flour. Vegetarians and vegans also need to ensure that they’re getting enough of certain essential nutrients, including iron, vitamin B12, vitamin D, calcium, zinc, and omega-3 fatty acids, since animal foods are the primary sources of these nutrients. Some people choose a lacto-ovo-vegetarian diet, which includes eggs, milk, and milk products; this dietary pattern
lessens your chances of having a calcium deficiency.
Some research has shown that a pescatarian diet, which includes fish along with an abundance of plant foods, may be even healthier than strict vegetarian eating. Such a plan also may be easier to stick to for people used to eating animal protein. If you just can’t give up burgers and steaks, make sure they’re the exception rather than the rule.
Practice Portion Control
Finding a dietary pattern that works for you is only part of eating healthy for your heart and brain. Even good-for-you foods can be consumed in excess, so you need to practice portion control. It’s not difficult to understand why most Americans eat too much: Beverages and fries at fast-food joints have been “super-sized,” and meals at many restaurants easily can feed two or three people. And many people don’t stop to consider if they are full; they just keep on eating until the food is gone. Add to this the fact that food is easily accessible for most Americans, and it’s clear why so many Americans are overweight or obese.
Here are a few tips to help you keep portions in perspective:
- Read food labels when grocery shopping. When a package says it contains more than one serving, measure out one serving into a separate dish. Not all serving sizes listed on Nutrition Facts labels reflect how much most people serve themselves, so don’t be fooled.
- Practice “mindful eating.” Take time to focus on and enjoy the tastes, textures, and aromas of your food. Avoid eating in front of the TV or computer or while using your tablet or smartphone.
- Serve food on smaller plates. Instead of using a dinner plate, substitute a luncheon plate or a salad plate.
- When eating at home, put reasonable portions of food on your plate and keep the rest of the food in the kitchen. Then, if you want to eat more, you’ll have to make a conscious decision to go get it. (What’s a “reasonable” portion? See our guide to portion sizes on this page.)
- When eating out, keep in mind that restaurant portion sizes are often at least double, and sometimes triple, the amount you should be eating. As soon as your meal arrives, divide it in half and box up one half, or share it with a dining companion.
Staying Hydrated
In addition to nutritious food, your heart and brain need plenty of fluids to function properly. You lose water every day through your breath, sweat, and urine, and you need to replenish what you lose. The Institute of Medicine says that, in general, women may need 91 ounces (about 11 cups) of water daily, and men may need 125 ounces (about 15½ cups) of water daily. That’s even more than the eight glasses of water per day you may have heard you need. Your diet contains many sources of water, however, including coffee, tea, and milk, along with fruits and vegetables, and even grains, poultry, and seafood, which all contribute to your daily fluid needs.
Most people can let thirst be their guide to adequate hydration without counting glasses of water. However, as you get older, you may need to pay closer attention to ensure you’re getting enough fluids, because your sense of thirst may decline with age. Be alert for signs that it’s time for a drink—urinating infrequently, less urine output than usual, dark-yellow or brown urine,
and/or a dry mouth.
Choose calorie-free beverages, such as water and unsweetened tea and coffee, to limit your intake of added sugar and empty calories. Low-fat and skim milk are other nutrient-dense choices with a moderate calorie count.
Questions on Diet Drinks
One way people cut down on calories in their beverages is by switching to artificially sweetened sodas. According to the U.S. Food and Drug Administration, “Food safety experts generally agree there is no convincing evidence of a cause-and-effect relationship between these sweeteners and negative health effects in humans.” Questions have been raised, however, about whether non-caloric sweeteners somehow might contribute to weight gain, and some studies have linked diet sodas and drinks to serious health problems.
One study did find that some people who drank diet soda daily were almost three times as likely to suffer a stroke and develop dementia as those who consumed diet soda weekly or less often. However, the media’s report of this study may have caused undue alarm.
Tufts expert Tammy Scott, PhD, cautions, “The results of this study show no dose response; that is, the people who drank two to six artificially sweetened drinks per day were not more likely to have a stroke than those who had only one a day. More importantly, while those who drank one a day were three times more likely to develop dementia, those drinking two to six per day did not have an increased risk over those who drank zero artificially sweetened drinks. Another concern is that when the investigators controlled for diabetes and obesity, the association between artificially sweetened drinks and stroke/dementia was reduced.” This finding could mean that people who have diabetes or are obese may be more likely to drink artificially sweetened beverages rather than sugar-sweetened ones, and it’s the diabetes and obesity rather than the beverages that raise the risk for stroke and dementia.
While the current evidence falls short of making the case to avoid all artificially sweetened beverages, such concerns do support advice to make water your first choice for staying hydrated.
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