To Eat or Not to Eat?
Ever heard something like this?
“Hi, have some nuts?”
“Oh, thank you, but nuts are full of calories and I’m on a diet.”
How can something so natural be so confusing? Well, a huge study (from Harvard, no less) is telling us that throwing down a handful, or more, of nuts may be one of the healthiest things you can do.
The study, published in the prestigious New England Journal of Medicine, involved more than 119,000 healthy volunteers. It found that those who regularly consumed at least a one-ounce daily serving of peanuts, walnuts, almonds, cashews and other tree nuts were 25% less likely to die from heart disease!
In fact, they had a 20% lower risk of dying from any cause (including cancer, heart disease, respiratory and even type 2 diabetes) during the three-decade long study compared to those who did not eat nuts. (Results improved the more nuts were consumed, up to 7+ times a week.) The study found that nut eaters enjoyed longer lifespans – even if they did not exercise, avoided fruits and vegetables, and were overweight.(1)
This is HUGE in Nutritional News!
Nuts have long been known to be healthy but there not any studies of this size and quality to provide hard-core evidence to prove it. Research on food (and diets in particular) is especially hard because it is difficult to single out the effectiveness of any one food.
However, in this huge study, senior study author Dr. Charles S. Fuchs said, “The reduction in mortality was substantial. I think eating nuts is comparable to other potentially beneficial lifestyle measures like exercise and avoiding obesity and trans fats.”
Some have complained about funding but The New England Journal of Medicine said, “We don’t ignore the funding source but it’s actually not one of the major issues in our decision-making process. We try to find the best science possible.”
Well, the study couldn’t entirely rule out all other factors – though they tried to take into account factors such as participant’s dietary habits, smoking status, and physical activity level. It is also backed by a long line of previous, smaller, studies that also suggest eating nuts confers health benefits. In fact, the FDA had already determined that there was enough evidence to say that eating 1.5 ounces of nuts each day “may reduce the risk of heart disease.”
Dr. Ying Bao, of Harvard, who led the study, said, “I’m fairly confident in our results. We have long known that nuts are nutritious foods filled with folate, potassium, fiber, good monounsaturated fats, and antioxidants.” (And most of us are aware that nut’s unsaturated fatty acids, minerals and other nutrients lower cholesterol and inflammation. This, alone, will help reduce many potential irritants to the body.)
As a Bonus, Nut Eaters Stayed Slimmer!
There are a lot of fat calories in nuts. But, the fact that nuts are an extremely natural part of life and our nutritional history on earth, forces us to take another look.
Most doctors, both conventional and alternative, recommend eating nuts. But nuts contain a lot of calories (about 170 calories per ounce) and many people love to snack on them. So are these tasty treats making us fat?
Dr. Ying Bao, of Harvard, said “There’s a general perception that if you eat more nuts you’re going to get fat. Our results show the opposite.” So what’s the deal?
Studies show that the more frequently people eat nuts, the less fat they are. Researchers at Purdue University conducted a review, published in the 2010 Journal of Clinical Nutrition, examining 43 studies, trials and surveys, covering over two hundred thousand human test subjects. They found that nuts are not fattening.
It appears that nuts – which contain a lot of fiber – have an appetite-suppressing effect. And when your appetite is suppressed, that obviously makes it easier to stick to a diet. Nuts might also have poor bioaccessibility, meaning that not all of their calories are absorbed.
How Can This Be?
Since we enjoy science, we understand that energy can neither be created nor destroyed. So if we are eating nuts and not gaining weight, then where do the nut calories go?
Dieters often give in to cravings, but eating nuts imparts a feeling of fullness. Therefore, snacking on nuts usually results in eating less at meal times. Adding nuts to the diet also reduces the feelings of deprivation that can accompany long-term dieting. Thanks to their high fiber, fat and protein content, nuts make you feel full and provide you with sustained energy levels. As a result, you’re less likely to overeat at subsequent meals.(2)
2. Increased metabolism
Evidence links regular nut consumption with greater resting energy expenditure, which is a fancy way of saying, “nuts increase your metabolism”.
The human body expends energy even while asleep in the service of basic functions like breathing, heartbeat and maintaining body temperature. This is called the Basal Metabolic Rate or BMR. Anything that increases the calories the BMR uses is called thermogenic. Nuts have been found to be quite thermogenic, owing at least in part to their high levels of protein and unsaturated fats.
One study analyzed by Mattes and his researchers showed that daily consumption of a moderate amount of peanuts over a 19-week period increased BMR by a whopping 11%.(3) Eating nuts would burn an extra 166 calories each day – and you would get to enjoy eating a daily dose of nuts.
3. Inefficient energy absorption
Although nuts are energy-dense (high in calories) the body doesn’t absorb all those calories. This is especially the case when eating whole nuts as compared to nut butters, implying that some of it has to do with how thoroughly the nuts are chewed. When whole nuts are consumed, much of their caloric value goes is not absorbed.
In fact, new research shows that 55-75% of the calories in nuts are not fully absorbed by the digestive tract. Nut calories are mostly excreted by your body and this is one of the reasons why nuts have been proven to help with weight loss and maintenance.(4)
This also applies, specifically, to the lipid fat content in nuts. Research reveals that up to 15% of the lipid content of whole nuts may be lost in your stool.(5, 6)
So, in a nutshell… nuts can be added to your diet without the fear of additional weight gain. A small handful eaten as a snack or sprinkled on a salad will boost your resting metabolism, lower your BMI and help you adhere to your diet. Roasted nuts are deep-fried in fattening, unhealthy oils, so instead choose raw, unsalted nuts for the healthiest option (or dry roasted nuts as the next best option otherwise). When eaten in moderation, nuts can be an important component of a successful weight loss program.
1. Ying Bao, M.D. Association of Nut Consumption with Total and Cause-Specific Mortality. N Engl J Med 2013; 369:2001-2011, November 21, 2013, DOI: 10.1056/NEJ Moa1307352.
2. Bes-Rastrollo M, Wedick NM, Martinez-Gonzalez MA et al. Prospective study of nut consumption, long-term weight change, and obesity risk in women. Am J Clin Nutr. 2009 Jun;89(6):1913-9.
3. Mattes RD, Kris-Etherton PM, Foster GD. Impact of peanuts and tree nuts on body weight and healthy weight loss in adults. J Nutr. 2008 Sep;138(9):1741S-1745S.
4. March 2012 issue of Oxygen Magazine.
5. Int J Obes (Lond). Peanut digestion and energy balance. 2008 Feb;32(2):322-8. Epub 2007 Oct 2.
6. Br J Nutr. 2007;v98:651-656. Effect of chronic consumption of almonds on body weight in healthy humans. At: http://www.drsarasolomon.com/do-you-eat-too-many-nuts/#sthash.R8NKBpp2.dpuf
Bes-Rastrollo M, Sabate J, Gomez-Gracia E, Alonso A, Martinez JA, Martinez-Gonzalez MA. Nut consumption and weight gain in a Mediterranean cohort: the SUN study. Obesity (Silver Spring) 2007;15:107-116
Bes-Rastrollo M, Wedick NM, Martinez-Gonzalez MA, Li TY, Sampson L, Hu FB. Prospective study of nut consumption, long-term weight change, and obesity risk in women. Am J Clin Nutr 2009;89:1913-1919
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