If you’re trying to lose weight, you could count your calories, keep track of precisely how much salt and sugar your eat, and make sure you hit certain targets for protein, carbohydrates, cholesterol and the various types of fat. Or you could set all of that aside and concentrate on just one thing: Eating at least 30 grams of fiber each day.

In a yearlong clinical trial involving 240 obese people who had metabolic syndrome, those who focused on fiber lost almost as much weight as those who followed the American Heart Association’s extremely detailed dietary recommendations. The average difference between the two groups — a mere 1.4 pounds — was too small to be considered statistically significant, according to a study being published today in the Annals of Internal Medicine.

The researchers who conducted the trial were quick to say that the American Heart Association diet is certainly effective. But it’s not necessarily user-friendly.

The AHA advises dieters to:

Eat at least 30 grams of high-fiber foods each day.

Eat fish twice a week.

Get protein from vegetables and lean meats.

Get 50 percent to 55 percent of calories from carbohydrates, 15 percent to 20 percent of calories from protein, and 30 percent to 35 percent of calories from fat (including just 7 percent of calories from saturated fat and less than 1 percent from trans fats).

Eat fewer than 300 milligrams of cholesterol per day.

Minimize sugar, sodium and sugar-sweetened beverages.

Drink no more than a moderate amount of alcohol.

If your head is spinning, you’re not alone. “The various AHA dietary recommendations may create adherence challenges,” as the study authors so politely put it.

They wondered what would happen if they emphasized the first item on that list and let the rest of them go. They had reason to think it might work: A 2012 study in Archives of Internal Medicine found that people who were advised to cut back on sitting and step up their consumption of fruits and vegetables improved their diet and exercise habits more than people who got specific instructions about increasing their physical activity and cutting back on saturated fats.