Study Links Nuts to Lower Body Weight and Risk of Obesity

01 Jul 2015 --- In a study published this week in Nutrition Journal* and funded by the International Tree Nut Council, researchers compared risk factors for heart disease and metabolic syndrome of tree nut consumers versus those who did not consume tree nuts.

Tree nut (almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts) consumption was associated with lower body mass index (p=0.004), systolic blood pressure (p=0.001), insulin resistance (p=0.043) and higher levels of high-density lipoprotein-cholesterol (good cholesterol) (p=0.022). In addition, tree nut consumers were 25% less likely to be obese and 21% less likely to have an elevated waist circumference than those who did not consume tree nuts.

The study looked at 14,386 men and women (19+ years) participating in the 2005-2010 National Health and Nutrition Examination Surveys (NHANES). Intake was from 24-hour recall data and tree nut consumers were defined as those who consumed ¼ ounce or more per day. "Approximately 6.8% of the study population consumed tree nuts," stated Carol O'Neil, PhD, MPH, RD, lead author on the paper and Professor at Louisiana State University Agricultural Center. "While that may sound small, it actually represents over 12 million individuals--a significant number." She added, "Those who consumed nuts ate about 1.5 ounces (44.3 grams) of tree nuts per day--similar to the amount recommended in the FDA qualified health claim for nuts and heart disease."

Research has shown that nuts can help reduce the risk of cardiovascular disease and metabolic syndrome (MetS). The latter is a cluster of risk factors for cardiovascular disease and type 2 diabetes and includes elevated blood lipids, blood pressure, blood sugar, insulin resistance and abdominal obesity. Obesity is also a risk factor for these two diseases and although tree nuts contain fat and calories, numerous studies have shown that diets "enriched with nuts" do not increase weight. Filled with plant protein, dietary fiber, and healthy mono- and polyunsaturated fatty acids, tree nuts are a satiating food that may actually help suppress appetite. Moreover, previous research by the same authors**, showed that tree nut consumption was associated with better nutrient adequacy for most nutrients that are lacking in the diets of many Americans, and with an overall better diet quality.

"Now that summer is here and people tend to be more active outside, tree nuts are a great, portable snack to take to camp, the beach or on a hike," states Maureen Ternus, M.S., R.D., Executive Director of the International Tree Nut Council Nutrition Research & Education Foundation (INC NREF). "Just 1.5 ounces of nuts per day (about 1/3 cup) can give you many of the important vitamins, minerals and energy you need throughout the day." Moreover, according to the 2011-2012 What We Eat in America/NHANES survey, snacks provided about 25% of daily calories.*** Choosing more nutrient-dense snacks, such as tree nuts, can have a positive impact on health.

* http://www.nutritionj.com/content/14/1/64 
** O'Neil, C.E., T.A. Nicklas, V.L. Fulgoni III, 2015. Tree nut consumption is associated with better nutrient adequacy and diet quality in adults: National Health and Nutrition Examination Survey 2005-2010. Nutrients. 7:595-607. doi:10.3390/nu7010595. 
***What We Eat in America, NHANES 2011-2012, individuals 2 years and over (excluding breast-fed children), day 1.