If you have trouble shedding belly fat, you’re not alone. For both men and women, the stomach is the most problematic area of the body when it comes to stubborn fat. That’s why about 54% of US adults suffer from central obesity (having a waistline of more than 40 inches in men and more than 35 inches in women).

Because getting rid of belly fat is so challenging, we went straight to the pros to find out their best-kept secrets for kicking that belly bulge to the curb. Check out the 10 tips they shared and say hello to a flatter stomach:

1. Avoid Diet Soda

Even though diet soda doesn’t contain any calories or fat, a study published in Diabetes Pro shows that people who drink diet soda gain weight. This is because diet sodas contain artificial sweeteners that confuse the body into thinking it is still hungry. Instead of drinking diet soda, opt for water infused with fruit.

2. Eat Your Afternoon Snack

Experts have found that eating three balanced meals and consuming one snack between 3 p.m. and 4 p.m. boosts the metabolism and regulates appetite. Instead of constantly snacking throughout the day, eat a protein-packed snack, such as a protein bar or Greek yogurt with berries, at this magical hour.

3. Eat Nuts

Research shows that eating nuts twice a week reduces weight gain. Walnuts are a particularly good nut to consume because they contain monounsaturated fats (MUFAs), which are great for reducing waist size and eliminating belly fat.

4. Ditch HIIT

Everyone says that high-intensity interval training (HIIT) is the best way for people to achieve their fitness goals. In a study published in the Journal of Obesity, however, researchers found that people who did HIIT gained abdominal fat over a 12-week period whereas people on the same diet who did aerobic exercise lost stomach fat.