- Whole, unskinned almonds are just as effective in a weight-loss diet as carbohydrate-based snacks, according to a new study.
- Participants in the study who either ate almonds or carbohydrate-rich snacks lost the same amount of weight.
- However, almonds may also provide some heart-protective cardiometabolic benefits that carbohydrate-rich snacks do not.
A new study from the University of South Australia suggests that a weight-loss diet can be just as effective when you replace carbohydrates with almonds.
Participants in the study, which was funded by the Almond Board of California, lost the same percentage of their body weight, 9.3%, on either an almond-snack or carbohydrate-snack weight-loss diet.
In the study, 106 individuals ranging in age from 25 to 65 years engaged in a three-month energy-reduction diet that reduced their energy/caloric intake by 30%, followed by a six-month weight-maintenance regimen. All had overweight or obesity at the outset of the study.
For snacks, 68 participants consumed 15% of their energy as 30–50 grams of unsalted, whole California almonds with skins — about 27 to 45 almonds. The researchers refer to this diet as the “almond-enriched diet,” or “AED.”
The other 72 individuals followed a nut-free diet (NFD) in which they derived 15% of their calories from carbohydrate-rich snack foods such as oven-baked fruit cereal bars and rice crackers.
At the end of both the three-month weight-loss period and the maintenance period, participants lost weight, gaining a higher percentage of lean mass at the end of the maintenance phase.
By the end of the two phases, both groups exhibited cardiometabolic improvements in fasting glucose, insulin, blood pressure, total cholesterol, LDL cholesterol, very low-density lipoprotein, and triglycerides, with an increase in HDL cholesterol.
The authors of the study hypothesize that these improvements are benefits of weight loss.
In addition, the group who snacked on almonds saw an improvement in lipoprotein subfraction concentrations.
The study is published in the journal
“Lipoproteins are particles made of fat and proteins that travel in the blood throughout the body,” explained first author Dr. Sharayah Carter. Some lipoproteins are harmful to one’s heart, while others are heart-protective.
“The reduction in harmful lipoproteins with weight loss in both groups was beneficial and associated with reduced cardiometabolic risk,” she said.
However, she added, “the greater reduction in the concentration of particular types of the lipoproteins — very small triglyceride-rich and small low-density lipoprotein particles — observed in the group who ate almonds is good news.”
These are lipoproteins linked to the development of atherosclerosis and cardiovascular disease.
Blood tests for cardiovascular risk
Dr. Carter noted that lipoprotein subfractions are not tracked in a standard physician-ordered blood test since they are a more sensitive and specific measurement of lipid metabolism and cardiovascular risk.
The two cholesterol measurements typically ordered by physicians are LDL — “bad cholesterol” — which stands for “low-density lipoprotein.” HDL — the “good cholesterol” — is the abbreviation for “high-density lipoprotein.”
“[Lipoprotein subfractions] are commonly measured in research studies as an emerging risk factor for CVD,” Dr. Carter pointed out.
A physician can still assess a patient’s health before and after a diet by testing blood pressure, fasting glucose to assess blood sugar control, fasting blood lipoproteins (total cholesterol, HDL and LDL, and triglyceride levels), body weight, and waist circumference.
Matching blood results against the Heart Foundation’s guidelines regarding CVD risk, the doctor can ascertain whether a diet has benefited a patients’ metabolic profile, or if they may have metabolic syndrome.
While nuts are high in fats, they also contain protein, are high in fiber, and are rich in vitamins and minerals. They place high on the list of the U.S. National Institutes of Health’s recommended foods.
“For people wanting to lose weight, it is possible to eat a diet that has lower energy and still be able to include almonds.”
— Dr. Sharayah Carter
“While there are some similarities with all nuts containing fiber, lignans, and L-arginine that are cardioprotective, almonds have more vitamin E and [fewer] calories and saturated fat per ounce than other nuts,” pointed out cardiology dietician Michelle Routhenstein, who was not involved in the study.
The current study is the largest to date that demonstrates that people lose as much weight snacking on almonds as they do on carbohydrate-based snacks, though other studies have come to the same conclusion.
The consumption of almonds has also been found to be negatively associated with adipose fat, or body fat, which is strongly linked to a higher CVD risk.
“Nuts are a core food in the Australian dietary guidelines and are rich in several essential nutrients, and snacking on almonds is a healthy alternative to processed snack foods,” noted Dr. Carter.
“I have no concerns with an almond-enriched diet such as this but it is important to note that many of these cardiometabolic and weight-loss targets were achieved due to the calorie-controlled diet plan. We need to be assessing what else individuals are eating to truly achieve optimal heart health.”
— Michelle Routhenstein
The authors note that the relatively small sample size of the study may not have been sufficient to expose more subtle between-group differences.
They also note that participants’ cardiometabolic indicators were within a healthy range from the beginning to the end of the study. They suggest future research might include individuals with type 2 diabetes, metabolic syndrome, or CVD to investigate larger cardiometabolic effects of weight-loss diets, including almonds.