Is Your Diet Making You Mad?

Eat, Exercise, and Lose Weight Without Mood Swings

It's torture for me to watch others indulge in things that I've deemed off-limits. When my husband uncorked the Cabernet, I felt my blood boiling right along with the water for the herbal tea I would be having instead. According to a study published in the Journal of Personality and Social Psychology, it's not the forgoing of food or drink itself but the act of resisting it that's so upsetting. In fact, the researchers found that exerting even a single act of self-control causes a significant drop in blood glucose levels. When blood sugar sinks, it can result in hypoglycemia, which can lead to symptoms that include feeling cranky and acting aggressive. Other studies found that deprivation ultimately backfires, leading us to binge on the very things we are trying to resist.

A simple way to prevent this, of course, is to steer clear of temptation in the first place. "Arrange your environment so that sticking to your eating plan requires as little willpower as possible," advises Sandra Aamodt, PhD, a neuroscientist and coauthor of Welcome to Your Brain. If ice cream is your weakness, don't keep it in the house. And if the office vending machine calls your name every day at 3 p.m., stock your desk drawer with good-for-you munchies like nuts and whole-grain pretzels.

Somer also suggests finding healthy replacements. Clearly, tea didn't quite cut it for me, but the good news is that in moderation treats like chocolate can qualify. In fact, recent research found that consuming 20 grams of dark chocolate twice a day for two weeks resulted in reductions in metabolic signs of stress, including levels of cortisol. "Dark chocolate is quite good for the brain," Dr. Ramsey says. "It is full of compounds that boost mood and concentration." I've also come up with calorie-free substitutions, like climbing into bed with a good book or a trashy magazine and replacing wine with an impromptu couples massage with my husband.

Working out is key to losing weight and staying upbeat -- no surprise there. Exercise prompts a change in brain chemicals that lifts your mood. And the effects are almost immediate, says Michael W. Otto, PhD, professor of psychology at Boston University and coauthor of Exercise for Mood and Anxiety. The pick-me-up can happen within just five minutes of completing a moderate workout.

Why, then, wasn't I euphoric after six consecutive days of tough sweat sessions? Because when it comes to the way exercise affects mood, more isn't necessarily better. "A workout that is too rigorous or lasts longer than 60 minutes can dramatically decrease blood sugar, which can affect mood and the ability to think clearly for days," says Michele S. Olson, PhD, a FITNESS advisory board member and professor of exercise science at Auburn University in Montgomery, Alabama.

To ensure that my activities take me to a happier place, Otto recommends being more mindful -- paying attention to how my body is feeling and not pushing too hard. "Ratings of mood during exercise can plummet as people get to the point at which it's hard to breathe comfortably," he explains, suggesting that I use the talk test. "If you can talk but not sing during an activity, you're doing moderate-intensity exercise. If you're not able to say more than a few words without pausing for a breath, you are doing vigorous-intensity exercise and should scale it back to maximize your mood." And Olson gives the A-OK to interval training as a way to boost the calorie-torching benefits of exercise without compromising mood. She suggests alternating 30 seconds of high-intensity cardio with 90 seconds of low-intensity. "In my research, interval training improved mood the most," Olson says.

All these new strategies have made a huge difference in my disposition. My husband comments on how cheery and resilient -- even freakishly enthusiastic -- I've become in the face of things that once stressed me out (like a.m. workouts), and my son is literally embracing the new me (no more mad Mommy equals a lot more hugs!). As if that weren't enough, the little guy supports my efforts by offering me healthy alternatives to gummy bears: "Here, Mommy, have some dark chocolate," he says, holding out a few squares. "It's good for you!" Indeed, as I'm sure he now realizes, sharing a treat like that isn't just good for me, it's good for the whole family.

Originally published in FITNESS magazine, March 2012.