Adult females who are dieting in order to lose weight, may find their pounds come off much more slowly if they have a snack between their breakfast and lunch, researchers from the Fred Hutchinson Cancer Research Center reported in the Journal of the American Dietetic Association. The authors suggest that a dietary weight-loss intervention should carefully consider the effects of timing, frequency, and snack quality on weight loss.

Anne McTiernan, M.D., Ph.D. and team carried out a 12-month long study and found that dieters who ate a healthy breakfast which was not followed by a mid-morning snack lost an average of 11% of their bodyweight, compared to only 7% for women who did snack between breakfast and lunch. In this study, a snack is any food or drink that is eaten or drunk between meals.

McTiernan said:

“We think this finding may not relate necessarily to the time of day one snacks, but rather to the short interval between breakfast and lunch. Mid-morning snacking therefore might be a reflection of recreational or mindless eating habits rather than eating to satisfy true hunger.”

Timing is important, McTiernan added. Snack too close to a meal, and you can sabotage your weight-loss plan, but having too long an interval between meals can also be bad if you want to lose weight.

McTiernan said:

“Snacking could be part of a dieter’s toolkit if they’re eating in response to true hunger. Individuals should determine if they experience long intervals – such as more than five hours – between meals. Adding a snack might help people deal better with hunger and ultimately help them to make more sound choices at their next meal.”

Some snacks can be unhealthy and ruin a weight-loss plan

The researchers discovered other surprising facts:

  • Women who say they have at least two snacks per day generally consume more fiber than others
  • Women who snack in the afternoon tend to consume a higher daily quantity of fruit and vegetables than those who do not nibble between lunch and supper

Their study is part of a larger randomized human study aimed at determining what effects nutrition and physical activity might have on breast cancer risk. It involved 123 post-menopausal women from the Seattle area; they were all overweight/obese, aged from 50 to 75 years. They were randomly selected into one of two groups:

  • Diet alone group – the aim was to consume between 1,200 to 2,000 calories per day, depending on their weight at baseline, with less than 30% of their daily calorie intake coming from fat
  • Diet plus exercise group – the same as above, plus five days per week of 45 minutes of moderate-to-vigorous exercise

All the participants received nutritional advice, but nothing was mentioned regarding snacking.

The participants had to record at what time of day they ate, as well as the percentage of calories from fat, fiber, and fruit and vegetables (a food-frequency questionnaire was used to make an estimate).

McTiernan said:

“Many people think that a weight-loss program has to mean always feeling hungry. Our study suggests that snacking may actually help with weight loss if not done too close to another meal, particularly if the snacks are healthy foods that can help you feel full without adding too many calories.”

The authors explained that several studies have shown that approximately 97% of Americans snack. Snacking is an American behavior that is widespread throughout all age groups. According to one survey which randomly questioned 1,500 adults, the most common snacks include crunchy and salty foods, such as nuts, pretzels, and potato chips, as well as cakes and cookies. Fruit and ice-cream are also very popular snacks.

Fruit Stall in Barcelona Market
Females who snack in the afternoon generally eat more fruit and vegetables than other women

The authors explain that “empty-calorie snacks”, such as sugary drinks and potato chips can seriously undermine any weight-loss plan.

McTiernan explained:

“Since women on a weight-loss program only have a limited number of calories to spend each day, it is important for them to incorporate nutrient-dense foods that are no more than 200 calories per serving. The best snacks for a weight-loss program are proteins such as low-fat yogurt, string cheese, or a small handful of nuts; non-starchy vegetables; fresh fruits; whole-grain crackers; and non-calorie beverages such as water, coffee and tea.”

In an Abstract in the journal, the authors concluded:

“These results suggest that snack meals can be a source for additional fruits, vegetables, and fiber-rich foods; however, snacking patterns might also reflect unhealthy eating habits and impede weight-loss progress. Future dietary weight-loss interventions should evaluate the effects of timing, frequency, and quality of snacks on weight loss.”

Written by Christian Nordqvist