You’ve set a health goal—to lose weight, increase your energy, boost your libido. So what approach will work better, diet or exercise?
It’s a no-brainer that diet and exercise are both crucial to your well-being and your waistline. And that generally adhering to recommended guidelines (like getting regular doses of aerobic activity and resistance training, filling half your plate with fruits and vegetables, and eating lean protein) is the best way to optimize your health overall. But what if you want to achieve something specific—to drop a dress size, say, or stave off heart disease? Research shows that, in certain cases, focusing on one over the other will give you better, faster results. Real Simple asked experts to consider five common goals. Here are their verdicts.
If You Want to Drop a Dress Size
Focus on diet: “It’s clear that you need to restrict calories in your diet to lose weight—and exercise to keep it off,” says Tim Church, M.D., the director of preventive medicine research at Louisiana State University, in Baton Rouge. “Most people who exercise to lose weight and don’t restrict calories shed only 2 to 3 percent of their weight over 6 to 12 months,” says Church. The reason? It’s much easier to deny yourself 500 calories a day—the amount you typically need to cut to lose a pound a week—than to burn that much through exercise. For instance, to work off almost 500 calories, a 155-pound woman would have to spend an hour pedaling a stationary bike at moderate intensity. Compare that with swapping a Starbucks Grande Caffé Mocha with 2 percent milk (200 calories without whipped cream) for a plain brewed coffee (5 calories) and eliminating a nightly bowl of ice cream (about 200 calories in a half cup) and a handful of potato chips (almost 160 calories). A bonus benefit of losing weight: Shedding about 5 percent of your body weight will reduce your risk of developing diabetes by almost 60 percent.
Take action: Eating fewer calories is pretty straightforward when you follow three guiding principles. First, stick with a primarily plant-based diet (fruits, vegetables, whole grains, beans, nuts, and heart-healthy fats, like olive oil). Second, limit processed foods (such as frozen meals, deli meats, and refined carbohydrates, including pastries and white bread), which contain lots of empty calories in the form of sugar and unhealthy fats (not to mention a lot of salt).
If you follow these two guidelines, you’ll automatically be doing a third thing that is linked to reduced calorie intake: eating more low-calorie–dense foods. High-calorie–dense foods (like full-fat cheese and red meat) pack more calories ounce for ounce than low-calorie–dense ones (like vegetables, fresh fruits, and whole-grain cereal). According to a study published in the journal Appetite, eating a low-calorie–dense diet (by decreasing fat, eating more produce, or adding water to recipes) helped people consume 230 to 396 fewer calories a day. “With these strategies, you’ll also be eating foods that are higher in fiber, so you’ll stay satisfied,” says Donald D. Hensrud, M.D., the chair of preventive medicine at the Mayo Clinic in Rochester, Minnesota. If you’re still not dropping weight, consider using an app, such as Lose It!, to track your calories. That way, you’ll be able to see what you’re consuming and where the calories are coming from.
If You Want to Increase Energy
Focus on diet: It’s true that exercise can give you an immediate surge of energy, but smart eating throughout the day will fuel you with a steadier supply. “With proper nutrition and well-timed meals, you’ll keep your blood sugar balanced. This is important, since blood sugar spikes and drops are a leading cause of energy fluctuations,” says Shawn M. Talbott, Ph.D., a nutritional biochemist in Salt Lake City and the author of The Secret of Vigor ($15, amazon.com). You’ll also help to balance your brain’s neurotransmitters, which are chemical substances (including serotonin, dopamine, and norepinephrine) that keep your mood up and therefore your energy from plummeting.
Take action: To maintain an even blood-sugar level, eat five to six times a day, or about once every three hours. In addition to your main meals, fit in two to three 200-calorie snacks. Ideal snacks contain lean protein, healthy fats, and complex carbohydrates—for instance, yogurt with granola, an apple with low-fat cheese, or peanut butter on crackers with a banana. Frequent eating can also help to reduce feelings of anxiety and depression (both of which can influence energy), since low blood sugar can increase your level of the stress hormone cortisol.
Another way to stave off fatigue is to load your diet with foods rich in flavonoids, like blueberries, blackberries, and acai juice. “Our research shows that flavonoids interact with receptors in the brain that lessen the perception of tiredness. So while they’re not necessarily energy-boosting, they are fatigue-reducing,” says Talbott. About half a cup of blueberries will do the trick. Another easy strategy? Drink water throughout the day. The sluggish feeling that you get late in the afternoon, which then drives you to the vending machine, is often your body telling you that it’s low in fluid, says Talbott. The best gauge of hydration is the color of your urine, which should be almost clear if you’re well hydrated. Keep a bottle of water nearby and sip it all day, and drink a large glass of water with every meal or snack.
If You Want to Reduce Your Risk of Heart Disease
Focus on exercise: According to an eight-year study published in the journal Circulation, women who were the most physically fit were the least likely to die from any cause, including cardiovascular disease, the number one killer of women in the United States. “Being fit is more important than weight or body mass index for heart health,” says Martha Gulati, M.D., the lead author of the study and an associate professor of medicine at Ohio State University in Columbus. In addition to helping you stay trim, exercise alleviates stress, lowers cholesterol, and increases blood flow. The three of them combined improve heart health more than diet alone does.
Take action: Aim to do aerobic (cardio) exercise, such as running or biking, for at least 150 minutes a week. The intensity should vary from moderate to vigorous so that you increase your cardiac capacity without overtaxing your body. Two times a week, also do a 20-minute session of resistance training, such as weight lifting. (These sessions can be done on the same days as the aerobic workouts or on alternate days.) Both types of exercise make your heart pump more blood, which strengthens it. Hate to exercise? Walking counts as cardio. Just be sure to wear a pedometer or an activity-tracking device (Gulati likes those from Fitbit), and shoot for 10,000 steps a day, or about five miles. “This amount ensures that you’re getting the minimal daily cardio-exercise recommendations,” says Gulati. To add resistance benefits, carry five-pound arm weights on your walks and include steep hills in your route.
And another thing: Sit less throughout the day. A 2012 study published in the journal Diabetologia revealed that the more sedentary you are, the more you increase your risk of heart disease (as well as diabetes). “When we sit for long periods, enzymes in the postural muscles change. This affects how the body metabolizes glucose and lipids, which leads to higher levels of bad cholesterol and glucose, among other things,” says Emma Wilmot, Ph.D., of the University of Leicester, in England, the lead researcher of the study. Avoid sitting for more than two hours at a stretch. To cut down on sitting time, stand during coffee breaks; set a timer to go off every hour, then get up and move around for a few minutes; or switch to a height-adjustable desk and stand periodically as you work.
If You Want to Keep Your Mind Sharp
Focus on exercise: The most compelling studies favor physical activity for mental acuity, says Gary W. Small, M.D., the director of the UCLA Longevity Center and a coauthor of The Alzheimer’s Prevention Program ($14, amazon.com). A study from the Annals of Internal Medicine found that people who were fitter at midlife had a 36 percent lower risk of developing dementia later in life than did their less-fit peers. “When people exercise, the areas that control memory, thinking, and attention increase in the brain,” says Small. “Regular exercisers also have less of the abnormal protein deposits in the brain that have been linked to Alzheimer’s.” That’s not to say that diet has no impact, says Small: “It’s just that the effects of exercise are more pronounced based on the evidence we have now.” Foods rich in omega-3 fatty acids (such as fish, nuts, and flaxseed) and antioxidant-rich fruits and vegetables (like strawberries and spinach) have been shown to improve brain health, while refined sugars and processed foods can have the opposite effect.
Take action: Aerobic exercise has always been regarded as critical to improving brain health, but strength training is also key. In fact, the two modes of exercise benefit the brain differently, which is why it’s best to do both. In a 2013 study published in the Journal of Aging Research, the authors found that both cardio exercise and strength training improved spatial memory (for example, remembering where objects were placed in a room) in women ages 70 to 80. Cardio alone improved verbal memory (for example, being able to remember a list of words after a distraction). And in a 2012 study from the Archives of Internal Medicine, women in their 70s who strength-trained improved their associative memory, meaning that they remembered pairs of pictures that they had been shown earlier. This is the kind of memory that allows you to remember two pieces of information at once, like picturing not just your keys but also where you placed them.
If You Want to Boost Libido
Focus on exercise: In a 2008 study in Obstetrics & Gynecology, almost 30 percent of women reported that they had experienced low libido in the past year. “Exercise is one of the best ways to improve body image, which affects libido,” says Heather Hausenblas, an associate professor of health sciences at Jacksonville University, in Florida, whose research focuses on exercise and body image. Libido is also affected by mood and self-esteem, and exercise can improve both.
Take action: All types of exercise can make you feel better about yourself, but yoga is one of the best for women with low libido, says Lori Brotto, an associate professor in the department of obstetrics and gynecology at the University of British Columbia, in Vancouver. Brotto, who conducts research on women’s sexual health and counsels women who struggle with such issues as low sexual desire and loss of arousal, says that studies have found that yoga helps to decrease stress and anxiety, induces a state of relaxation, and helps women to remain focused—all of which can improve sexual health. She adds that strength training can also help tone perceived trouble spots and help women “feel more comfortable about being touched.”