Substituting almonds for less healthy foods could help dieters stick to a kilojoule-controlled diet, and lower their cholesterol at the same time, researchers say.
"Nuts, and in this case almonds, shouldn't be on the 'do not eat' list, they can be effectively incorporated in a weight loss plan, with the caveat that they have to be portion controlled," said Dr Gary Foster, who led the study at Temple University in Philadelphia.
The new study, published in the American Journal of Clinical Nutrition and supported by the Almond Board of California, involved 123 generally healthy but obese people who followed a kilojoule-controlled diet for 18 months. Women ate 5 040-6 300 kilojoules per day, while men ate 5 040-7 560kJ.
Half the participants were randomly assigned to eat two 28-g packages of almonds (about 24 almonds per pack) each day - or about 1470kJ worth. The remaining subjects agreed to avoid nuts altogether. Six months later, the nut-free dieters had lost slightly more weight than the almond eaters: 7.2 vs 5.4kg , on average.
By 18 months, however, both groups had gained some of their weight back, and there was no longer a clear difference in total weight loss between participants who did and didn't eat almonds.
Almonds cut heart disease risk
Past research also suggests that nuts like almonds might play a role in reducing risk factors for heart disease, so Dr Foster and his team expected to see some improvement in cholesterol and triglycerides among the almond-eating dieters. And indeed, six months into the study, cholesterol in the almond group had fallen by 8.7 mg/dL on average, compared to 0.1 mg/dL in the nut-free group. Both groups were under the 200 mg/dL limit for total cholesterol recommended by the Centers for Disease Control and Prevention.
After 18 months, cholesterol levels had risen in both groups but were still lower, on average, in the almond group - although the difference was not statistically significant."This shows you can include almonds in the context of a weight control programme, lose a significant amount of weight and get nice additional benefits in terms of cholesterol and triglycerides," said Dr Foster.
Still, he urges caution. "Almonds don't make you lose weight; they're not free kilojoules," he said. It can be difficult for dieters to stay on track for as long as 18 months, and healthy people have fewer incentives to lose weight than those with health problems, said Dr Michelle Wien, a nutrition researcher at Loma Linda University in California, who wasn't involved in the study.
In their report, researchers point to a lack of difference in blood fats at the end of the study as evidence that participants stopped following the diet over time. That's normal in any type of weight loss program, said Dr Wien. Snacks like nuts - promoted as a healthy source of nutrients by the US Department of Agriculture - are generally considered off-limits to dieters because of their high fat content.
Almonds high in vitamins
Almonds are particularly rich in magnesium, potassium and vitamin E, as well as being a good source of fibre and calcium, according to the study's funder, the Almond Board of California. When dieters are limiting how many kilojoules they eat, it's important they eat foods that are nutrient dense, with a nice level of vitamins and minerals, and good quality fats, said Dr Wien.
It's a comfort for people who are struggling with weight management, said Dr Wien. They often crave something crunchy, something palatable with a nice texture, she added. The message to dieters is not 'eat all the almonds you want and you'll lose weight,' but you can effectively incorporate almonds as part of a weight controlled diet," said Dr Foster.
(Reuters Health, Natasja Sheriff, July 2012)
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