By Janis Jibrin, M.S., R.D., Best Life lead nutritionist

If soft drinks are a staple of your diet, you may be wondering how you’re going to make it through Phase 2 of the Best Life Diet, where those beverages are off-limits. How's this for motivation? One study suggests that as little as one soda daily jacks up your risk for a dangerous medical condition.

The average American adult—ages 19 to 50—guzzles about 2.5 sodas daily (this number drops to about 1.5 sodas after age 50), according to USDA surveys. Based on recent research, that's 2.5 sodas too many. In fact, drinking as little as one soda daily is associated with a 50 percent increased risk for developing metabolic syndrome, shows a study in the scientific journal Circulation. Metabolic syndrome is the term given to a cluster of conditions, including high blood sugar, high blood pressure, high levels of a blood fat called triglycerides, low levels of HDL ("good" cholesterol), and a large waistline (35 inches or more for women, 40 inches or more for men). Obviously, if you have metabolic syndrome, you're also more likely to develop heart disease or diabetes.

You may be thinking that you're off the hook if diet soda is your drink du jour. But the researchers discovered that diet soda was just as risky as regular. According to the study, one soda daily—whether it's diet or regular—will increase your chances of developing metabolic syndrome.

What's the link between diet sodas and disease? Researchers aren't sure, but speculate that the sweet taste may lead people to crave—and eat—more sweets. Or that caramel, a common ingredient in diet and regular sodas, may form "glycation products" in the body. These are clumps of sugar and protein, which are linked to insulin resistance (the first step to diabetes) and inflammation (a risk factor for heart disease and other ills).

This is just the latest in a slew of studies linking soft drink consumption to an increased risk for obesity in both children and adults. Other studies show that soda drinkers are more likely to suffer from tooth enamel erosion, and possibly even diabetes.

There is a fix for your fondness for fizz. You can wean yourself off soda! If it's the carbonation you crave, try sparkling water. Personally, I like the lemon or lime-flavored waters. When you want a little sweetness, mix sparkling water, plain water or seltzer with a little fruit juice. (About four to six ounces—or 60 calories—of juice count as one of your two daily fruit servings. Ideally, you should go for whole fruit, which contains more fiber, but it's OK to use juice to hit that goal once in a while.) Other good choices include unsweetened iced tea, such as Lipton Pure Leaf Unsweetened in a glass bottle; fat-free or 1 percent milk; hot tea or coffee.

If you've been drinking lots of regular soda nearly every day, and going without any soda will make you feel deprived, then switch to one diet soda per day. (As we all know, deprivation is dangerous, too!) Meanwhile, sip on the healthier substitutes listed above. Eventually, try weaning yourself off even diet soda completely, or at least make it an occasional treat.