Is going gluten- or dairy-lite worth it?

Read this if you're debating the body benefits of cutting back versus cutting out.

Say you’ve been feeling lethargic or bloated. You have a hunch that gluten or dairy could be to blame, but you’re not willing to give up either completely. You still want to enjoy the occasional bowl of pasta, you can't imagine your morning coffee without a splash of milk. Plus, there are some drawbacks to a too-clean diet. But will your body only reap the benefits of elimination if you cut something out completely, versus cutting back?

Not necessarily. “I definitely think that if your intolerance to dairy, gluten, soy, or other common trigger foods isn’t severe, you’ll see benefits if you cut back on them,” says Carolyn Brown, R.D., a nutritionist at Foodtrainers in New York City. “I tend to put all my clients on diets without a lot of gluten, because eating a lot of wheat is like eating only carrots and no other vegetables—too much of anything isn’t good.”

Brown names exhaustion, puffiness, a sallow or unclear complexion, low energy, bad moods, and headaches as signs that certain foods may not be doing your body any favors. “When people first started going gluten-free, it was about weight loss,” she says. “But now it’s about the immeasurables: Is it easy for you to wake up in the morning? Are you sleeping soundly?”

If you do have a sensitivity to something, eating it can irritate and even damage the cells lining your gut. It can also mess with your hormones, causing inflammation that triggers your body to release cortisol in unhealthy amounts. If you suspect that a certain food doesn’t sit well with you, Brown recommends eliminating it for three weeks to see if you feel better afterward. If it turns out that you have a hard time digesting, say, dairy, and you don't want to go cold-turkey, you can experiment with introducing relatively low-lactose mozzarella and Swiss in place of cheddar or goat’s milk yogurt or ice cream instead of the cow’s milk kind.

But be sure not to get so focused on a single ingredient or nutrient that you lose sight of the big picture. “If you decide to cut out wheat and start eating all the gluten-free foods you want, you won’t get great results,” says Brown. “A gluten-free donut is still a donut.”