They’re crunchy, tasty, and nutritious. Nuts give salads and other food dishes a kick. They’re great as a garnish on pies, cakes, and even chocolate. They also make a tasty and convenient snack.
So nut lovers galore were undoubtedly thrilled with the recent news that nuts are actually lower in calories than once thought. According to researchers, many nuts are 16 to 25 percent lower in calories than currently listed in the USDA nutrient database.
This news has led some companies, such as KIND, to change their nutrition facts labels to reflect the lower calorie counts, as Forbes columnist and obesity Bruce Y. Lee reported.
How is it that scientists overestimated the calories in nuts? It’s simple. The way calories are measured for various tree nuts has changed, as Dr. Lee points out. For years, food manufacturers relied on something known as the “Atwater system” or its derivatives to determine the available energy (calories) in foods. This system works by taking the average calorie counts for nutrients like protein, carbs, and fat that was once determined by burning them and then multiplies the averages by the nutrient content of the food item of interest.
If that sounds complicated, think of it this way. You have a portion of food containing 10g of protein, 20g of carbohydrates, and 9g of fat, which translates via the Atwater system to 201 calories. The carb count used in the Atwater calculation is the total carbohydrates minus the fiber content because most fiber is insoluble (indigestible) and runs right through you, figuratively speaking. Digestible and nondigestible fiber is commonly known as fiber, respectively. The main difference between soluble and insoluble fiber is its ability to dissolve in water. Soluble fiber readily dissolves in water and is thus easily digested; insoluble fiber absorbs water as it passes through the digestive system and has little impact on metabolism.
If that sounds complicated, think of it this way. You have a portion of food containing 10g of protein, 20g of carbohydrates, and 9g of fat, which translates via the Atwater system to 201 calories. The carb count used in the Atwater calculation is the total carbohydrates minus the fiber content because most fiber is insoluble (indigestible) and runs right through you, figuratively speaking. Digestible and nondigestible fiber is commonly known as fiber, respectively. The main difference between soluble and insoluble fiber is its ability to dissolve in water. Soluble fiber readily dissolves in water and is thus easily digested; insoluble fiber absorbs water as it passes through the digestive system and has little impact on metabolism.
The drawback of the Atwater system is that it sort of lumps together different foods that happen to provide a given nutrient. Food is complex and doesn’t merely exist in broad nutrient categories. Structure, form, gut flora composition, and many other factors beyond simple nutrient composition affect how the body processes food.
In the last decade, three research scientists, David J Baer, Janet A Novotny, and Sarah K Gebauer, from the U.S. Department of Agriculture (USDA), have made serious inroads into explaining what happens to nuts during digestion. In an American Journal of Clinical Nutrition study, the three researchers fed 18 healthy adults either a “controlled diet” or “an almond-containing diet” for 18 days. They then did what you always do if you’re a scientist after you feed someone. They collected their pee and poop. The researchers wanted to know how much of the almonds were actually metabolized and converted into energy versus how much ended up in the toilet.
Based on these measurements, they determined that almonds contain, on average, 4.6 calories per gram, or 129 calories per 28-gram serving. This is about 23 percent less than what’s calculated by the Atwater method (i.e., 6.0 to 6.1 calories per gram or 168 to 170 calories per serving.) That would be about a 23 percent to 24 percent drop in the calorie count for almonds. In other words, the Atwater method may be overestimating the energy content or calorie counts of almonds by 32 percent, notes Dr. Lee.
The USDA trio did something similar for another popular tree nut: walnuts. As reported in the Journal of Nutrition, they determined the walnut calorie count to be 21 percent less than the Atwater method calculation. The researchers also tried the same approach for cashews and found that the calorie count was 16 percent lower than what is typically found via Atwater, on nutrition labels, and elsewhere.
The study findings are further evidence that nutrition is a lot more complex than previously or even currently understood. Indeed, no single measure can tell you everything about a food item. And better understanding and appreciating this complexity should be a priority, particularly with obesity and overweight rates now at epidemic proportions.
SHOULD YOU EAT NUTS?The study findings are further evidence that nutrition is a lot more complex than previously or even currently understood. Indeed, no single measure can tell you everything about a food item. And better understanding and appreciating this complexity should be a priority, particularly with obesity and overweight rates now at epidemic proportions.
This should all come as welcome news if you love nuts but worry about their caloric content. As I said before, nuts such as almonds, walnuts, and cashews are a good source of fiber, antioxidants, protein, and nutrients such as vitamin E, magnesium, phosphorus, copper, manganese, and selenium.
So, while nut lovers everywhere are rejoicing (a 25-calorie drop is nothing to sneeze at), I need to add a word of caution. I seldom suggest to my patients that they count calories, even though they’re part of any weight-loss equation. What I advise instead is that they count “calorie units,” a term coined by my colleague, Dr. Stephen Gullo. What’s important to people looking to lose weight isn’t necessarily the calorie count in 2-3 potato chips or one Oreo cookie, but how many potato chips or cookies a person eats. At 50 calories, a single Oreo cookie isn’t going to derail anyone’s weight loss goals. However, if that single cookie activates or reactivates cravings for more cookies, then that single Oreo could quickly turn into thousands of calories.
Though nuts contain fewer calories than once thought, they’re easy to overeat. Think of it this way. The USDA RDA (recommended dietary allowance) is about 7-8 nuts per day. That’s a fine amount in theory, but how many people count 7-8 nuts and stop? This is especially true if they’re eating them right out of a bag or bowl. Most people eat nuts by the handfuls, just as they do other crunchy, bite-sized snack foods. “Just a few” nuts can quickly add up to several handfuls! The advice to eat just a few nuts is what Dr. Gullo, calls “good nutrition but lousy psychology.”
On the other hand, a carefully controlled portion (1-2 tablespoons) of chopped nuts sprinkled on a salad or Greek yogurt can add flavor and crunch, which might even be beneficial for weight loss because it improves the overall eating experience and may keep you from feeling deprived, the number #1 killer of most diet programs.
My suggestion: Have your nuts but first recognize your eating habits and patterns. If you have a history of overeating nuts, then they might not be the best choice, no matter the calorie count or purported health benefits.
My suggestion: Have your nuts but first recognize your eating habits and patterns. If you have a history of overeating nuts, then they might not be the best choice, no matter the calorie count or purported health benefits.
Source: http://bit.ly/32uO8vV, http://bit.ly/3cg8cq8
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