You think you’re doing the right thing reaching for a sandwich instead of a cheeseburger? Well, it all depends on what’s between those pillowy slices.

BEST: Avocado- Filled with heart-healthy fats, they also provide anti-aging, disease fighting antioxidants and nearly 20 different vitamins and minerals.

BEST: Hummus- Try two tablespoons of hummus instead of mayo as your sandwich spread to cut calories, and to add bonus nutrients, vitamins, minerals, and antioxidants.

BEST: Basil- Fresh basil has potent anti-inflammatory effects, which keeps away premature aging and chronic diseases, including obesity.

BEST: Onions- In addition to fighting inflammation, onions help fight heart disease by protecting blood vessels and reducing cholesterol.

BEST: Vinegar- Low in calories, packs antioxidants, and its main component, acetic acid, has been shown in research to help control blood pressure and blood-sugar levels while curbing fat accumulation.

WORST: White bread- A recent Spanish study found that those who ate only white bread -- two or more portions a day – were 40% more likely to become overweight over five years, compared to those who ate less than one portion of white bread a week.

WORST: Processed meat- High in calories, fat, and sodium -- A large European study concluded there’s a solid link between the consumption of processed meats and heart disease, cancer, and the risk of death.

WORST: Ranch Dressing- A two-tablespoon portion packs 130 calories and nearly 400 mg of sodium. Try whipping up a cleaner version made with nonfat organic plain yogurt, a touch of Dijon, lemon juice, minced garlic, black pepper, and Italian herbs.

WORST: Imitation cheese- Filled with additives like corn syrup, sugar, salt, and preservatives, packing 100 calories and 500 mg of sodium, it’s not worth it. Try natural cheese or guacamole instead.

(Source: Yahoo! Health)