We asked a dietitian what you should — ​and shouldn't​ — do if you want to look and feel healthier in a week

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Didn't make it through all of your fitness and diet goals in time for summer? Don't fret.

There are still plenty of things you can start doing now to start looking and feeling healthier.

Sure, you're probably not going to wake up looking like an underwear model tomorrow — but you can certainly start feeling better and improving your digestion in a week, according to registered dietitian and nutritionist Andy Bellatti.

Here are a few things Bellatti and other nutritionists recommend.

DO: Drink lots of water.

Water is essential — it regulates the shape of every cell inside our bodies. If we don't get enough, in fact, these cells begin to shrivel up.

The Centers for Disease Control and Prevention recommends choosing water instead of sugar-sweetened beverages to "help with weight management." Swapping a cold glass of H2O for a single 20-ounce soda will save you about 240 calories.

So hydrate, Bellatti told Business Insider. "Ideally with water." Not a fan of the absence of flavor? He suggests spicing it up with a few slices of lemon, lime, or cucumber.

DON'T: Drink only water — or any other beverage.

If you're considering a "detox" or "juice cleanse," you might want to reconsider. Drinking just water, juice, or any other liquefied concoction for more than a few days can set you up for unhealthy eating behaviors, and can often lead to unhealthy spikes and drops in blood sugar levels, which can spawn cravings and mood swings.

"This is a recipe for 'hangriness,'" says Bellatti, "that also inaccurately paints all solid food as problematic."

DO: Cut back on sodium.

Most of us — 89% of adults, according to the CDC — eat too much sodium, band that's not including any salt added at the table.

While salt intake remains a hotly debated health topic, eating too much of it is linked with puffiness and bloating, according to Harvard Health. Depending on your diet, cutting back on sodium can be an easy ways to start feeling better.

"Sodium retains water," says Bellatti, "so lowering sodium intake also reduces puffiness."