Americans spend millions each year on fad diets, trendy fitness programs, and pills to lose weight. But here’s an easy, effective, and cheaper way health experts say is a slam-dunk trick for shedding pounds: Simply use a smaller plate.

A new analysis published in the Journal of the Association for Consumer Research has found that smaller plates can help reduce the amount of food a person eats — with a few caveats.

For the review, researchers examined 56 previous studies, and found that overall, smaller plates can help reduce consumption under specific conditions.

Factors evaluated in the analysis:

• Type of food consumed — snack foods, popcorn, ice cream, breakfast cereal, rice, vegetables, fruit, etc.
• Type of plate — bowls vs. plates, serving platter vs. plate from which the food is consumed.
• Portion size — fixed amount of food served, amount varied in line with the plate-size, or self-served portions.
• Setting — consumers invited to a food laboratory vs. unaware consumers in natural settings such as a buffet.

In general, the studies showed that using plates that are half the normal size prompted volunteers to eat an average of 30 percent less food.

The researchers found that small plates worked best if people served their own food. They also found that smaller plates worked best if consumers weren't aware their actions were being monitored.

Overall, the research shows that simply switching to smaller plates can help curb overeating among individuals who serve themselves, either at the dinner table or at a buffet.

"Just changing to smaller plates at home can help reduce how much you serve yourself and how much you eat," says co-researcher Natalina Zlatevska of Bond University, Australia.

Another study published this week also found that the size of a dinner table may also influence how much we eat. This new study, published in the Journal of the Association for Consumer Research, found people ate less when food was served in smaller portions and placed on a large table and ate most when large portions were served on a small table.

For the study, the researchers divided four large round pizza pies of the same size into regular-sized slices (eighths) or smaller slices (sixteenths). They then placed two pies on small tables that were just a little bigger than a pizza pie. And they placed the other two pies on large tables that were much bigger than a pizza pie.

They then asked 219 university students to one of the four tables and invited them to take as much pizza as they would like to eat.

Those at small tables took about twice as many slices as people at large tables. In other words, people who saw a pizza pie with smaller slices took about same number as those who saw one with regular slices when served on a large table. This meant they ate at lot less pizza overall.

"To eat less food," lead researcher Brennan Davis recommends, "serve food in small portions and on large tables."

Other simple tricks to help you drop extra weight include:

Weigh yourself daily. A study published in the Public Library of Science journal PLOS ONE found that the more dieters weighed themselves, the more weight they tended to lose. Those who went more than a week without weighing themselves gained the most weight over the course of the study.

Chew food thoroughly. A recent study found that people who were at an ideal weight chewed their food almost 40 times before swallowing, while those who were overweight chewed less than 10 times before swallowing.

Drink before eating. Studies show that people who drink a lot of water while dieting lose more weight than people who don't. In fact, one study found people who drink a glass of water before each meal tend to eat less. "Water makes your stomach feel fuller, suppressing your hunger as well as your overall caloric intake," says nutritionist Elizabeth DeRobertis.