Grain Bars Before Dinner Aid Weight Loss

a grain bar

A humble grain bar could be the answer to your weight loss woes.

New research published today may cause a bit of a stir in the nutrition and weight loss communities. It seems that eating grains (yes, the high carb, high energy food that is apparently really bad for us) may actually aid weight loss. In an 8 week study which compared consumption of peanuts, grain bars and water 1 hour before a meal, it was found that those who ate a grain bar experienced “significant weight loss“.

It had already been established that peanut consumption reduces hunger and therefore helps you to eat less. This study looked at the effects of eating peanuts and grain bars on postmeal satiety (how hungry you feel after your dinner) in adults of a healthy weight and those overweight. Also, glycemia (blood sugar levels) was recorded.

Who Was Studied?

The study followed 59 people, 15 of whom had an average age of 28 1/2, and an average body mass index (BMI) of 23.1 kg/m2 (the healthy weight group) , and 44 people with an average age of 40 1/2 and average BMI of 31.8 (the overweight / obese patients).

What Did They Eat?

Each person either had an isoenergetic peanut snack (packets of peanuts, 1 oz / 28g, 170 kcal), a grain bar (1.4 oz / 40g, 140 kcals) or water, one hour before eating their main evening meal, which was a set test meal. The healthy weight group had their blood sugar levels recorded at 30 minute intervals after eating. The overweight group continued with the regime for 8 weeks.

In the 8 week study, body mass index was measured every 2 weeks. Daily calorie consumption was recorded. Blood analysis was also carried out before the trial, after a week and again at the end of the trial.

What Happened?

Those who ate the grain bar before their meal experience increased satiety (fullness) after eating, more so than those who had peanuts. What was most surprising was that although blood glucose levels were higher an hour after eating in the grain bar group, after 2 hours had passed blood glucose levels did not vary between the two groups.

In the 8 week trial of overweight people, those who ate the grain bars ate on average 458 Calories a day fewer than those who ate peanuts. Also Hemoglobin A1c levels (used to determine blood sugar control) in the grain bar group fell significantly. Those who ate grain bars experienced significant weight loss.

What Does This Mean?

The research paper concluded with the following statement:

“A low-energy, glycemic carbohydrate preload to the evening meal reduced 24-h energy intakes in healthy, overweight adults, resulting in significant reductions in body weight”.

There are 3 important conclusions from this study:

  1. Eating grain bars significantly reduced hunger and allowed people to eat around 450 Calories a day less without really trying – they were naturally fuller after eating.
  2. Eating grain bars can actually lower blood sugar levels and help to manage type 2 diabetes.
  3. Controlled snacking can help manage weight.

This is really a surprise result. So many nutritionists advise to reduce grains completely and increase the consumption of low GI foods. Nuts are often cited as being an excellent source of low GI carbs, high protein and healthy fat. However, this research suggests that eating more grains, when they are eaten an hour before a meal can reduce hunger, aid weight loss and keep blood sugar levels under control.

Important note: The grain bars were made by Target, who make the Kellogg’s Nutri-Grain bars. The research was supported by a grant from the National Peanut Board, Atlanta GA.


“The effect of peanut and grain bar preloads on postmeal satiety, glycemia, and weight loss in healthy individuals: an acute and a chronic randomized intervention trial” by Carol S Johnston, Catherine M Trier and Katie R Fleming. Nutrition Journal 2013, 12:35 doi:10.1186/1475-2891-12-35. Published: 27 March 2013.

Link to Provisional PDF: The effect of peanut and grain bar preloads on postmeal satiety, glycemia, and weight loss in healthy individuals: an acute and a chronic randomized intervention trial.

More like this in the Diet and Nutrition section

  1 comment for “Grain Bars Before Dinner Aid Weight Loss

  1. ann
    May 13, 2013 at 6:33 am


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