Carbo Loading Do You Overdo Refined Grains?
Eat less sugar. Check. Eat more whole grains. Check. Eat less refined grain. Check.
Or maybe not. Many people would be surprised to know just how much refined grain they consume.
An adult who eats 2,000 calories a day should swallow no more refined grain than you’d get in three small slices of bread, says the U.S. Department of Agriculture. (And there’s good evidence that less is even better.)
Yet you’d get at least double that day’s worth in a single restaurant serving of pasta, pancakes, pizza, pad Thai, or virtually any dish served with rice or noodles at a Chinese restaurant.
In 1970, the average American consumed about 430 calories a day from grains (wheat, rice, corn, oats, etc.), according to the U.S. Department of Agriculture.
By 2008, we were up to 625 calories a day, a huge bump (see “Grains on the Rise”). And roughly 90 percent of the grain we eat is refined, not whole. Only one other category—fats and oils, which includes butter, oils, margarine, and shortening—supplies that many calories. (So much for the popular notion that we’ve been on a low-fat diet.) Added sugars also climbed, though less so. They’re up by about 60 calories a day since 1970.
How does so much refined grain creep into our diets? Restaurants pile on the pasta, rice, pancakes, breads, and other cheap carbs (see “Step Away from the Carbs,” p. 5).
If you go to a Mexican restaurant and get a burrito, if you go to a Chinese restaurant and get rice, if you get a huge plate of pasta and huge pieces of bread, you’re eating well over the amount that’s recommended all day,” says Penny Kris-Etherton, Distinguished Professor of Nutrition at Pennsylvania State University.
Many restaurants combine multiple carbs into one meal. That burrito stuffs rice into a tortilla. And that’s after you dive into the free basket of Tortilla chips or polish off a cheese quesadilla appetizer.
Like many Italian restaurants, Olive Garden offers unlimited bread with your pasta. That often follows an appetizer Like bruschetta (on white bread) or artichokespinach dip (with white bread) or fondue (with white bread). And no one’s offering wholegrain chocolate cake or tiramisu for dessert.
It’s not just restaurant food. We’re eating bigger bagels, muffins, doughnuts, scones, ice cream cones, pretzels, cookies, wraps, and slices of bread (most of which are made with white fl our).
“People see bread labels that say ‘15 different grains,’ ” says Kris-Etherton. “They think, ‘Wow, this is super.’ ” They don’t notice that each slice has 100 to 120 calories. And a bagel can easily have 300 calories.
“But if you look at a thin slice of bread, which has 70 calories, that’s what we used to eat before,” notes Kris- Etherton. Now 70-calorie slices are called “small.”
Why are we eating oversized breads, bagels, burritos, and rice bowls? In part, it’s because flour and rice are cheap. Restaurants look generous when they pile them on our plates, and we eat what’s there. After a while, the servings don’t look oversized anymore.
And our alarms don’t seem to go off, as they might for sweets or fried foods.
“The danger is that some people are assuming they can’t get fat from carbs like bagels, pretzels, and spaghetti,” Says Alice Lichtenstein, director of the Cardiovascular Nutrition Laboratory at the Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University in Boston.
Perhaps we’re more focused on avoiding saturated fats and added sugars. Both steps are crucial. Saturated (and trans) fat raises the risk of heart disease. Added sugars are empty calories that may promote obesity, heart disease, diabetes, and gout (see “Sugar Overload,” Jan./Feb. 2010).
“Roughly 35 percent of our calories are coming from SoFAS—solid fats and added sugars,” says Kris-Etherton. “We’re eating way too many added sugars. But we also have to be mindful of the amount of refined grains we’re eating.” Here’s why.
1. Too many carbs can raise triglycerides and lower HDL (“good”) cholesterol.
For some people, too many carbohydrates of any kind may threaten the heart.
“Toward the end of the 1990s, we realized that some people on very-high-carb diets were developing dyslipidemia,” says Lichtenstein. Those carbs were mostly coming from added sugars and refined grain.
The “dyslipidemia” was a mix of high triglycerides (at least 150 mg/dL) and low HDL (under 50 for women or under 40 for men). “Both are associated with an increased risk of cardiovascular disease,” notes Lichtenstein. “They move in lockstep.”
Genes make some people more susceptible to having high triglycerides and low HDL, but the obesity epidemic has made the problem worse. “You’re more likely to develop dyslipidemia if you’re overweight,” says Lichtenstein. “And we certainly aren’t getting slimmer.”
High triglycerides, low HDL, and a large waist (over 40 inches in men or 35 inches in women) are three of the five signs of the “metabolic syndrome.” The other two are elevated blood pressure (at least 130 over 85) and elevated blood sugar (at least 100 mg/dL).1
“Approximately 47 million Americans have the metabolic syndrome,” says Kris-Etherton. That’s one out of every four adults.2
“It may soon surpass cigarette smoking as the numberone risk factor for cardiovascular disease,” she notes.
People with the metabolic syndrome also have a higher risk of diabetes.
Extra carbs may matter even if you don’t have the metabolic syndrome. (You need three of the five signs to have it.)
“People who have either high or average triglyceride levels experience an effect of carbohydrates,” says Frank Sacks, professor of cardiovascular disease prevention at the Harvard School of Public Health in Boston.
“When we tested overweight or obese people, carbohydrates raised their triglycerides unless their triglycerides were really low.” (He’s talking about levels under 100 mg/dL.)
Do some carbs raise triglycerides more than others? Sugars appear to raise them the most.3 Beyond that, it’s not clear whether refined grains raise triglycerides more than whole grains.
“Is the amount or the type of carbohydrate the most important thing?” asks Sacks. “That’s a critical question.”
So far, the evidence is skimpy. For example, the British WHOLEHeart Study found no difference in triglycerides (or HDL) when roughly 300 overweight men and women were told to eat two to four ounces a day of whole grains instead of refined grains for several months.
And when Stanford researchers assigned 120 adults to eat more whole grains, beans, and vegetables instead of refined grains and sugar, they saw no difference in triglycerides (or HDL).5
“Do whole grain and refined grains have equal effects?” asks Sacks. “That’s what our current research is trying to find out.”
2. Limiting refined grains can help lower blood pressure.
If you don’t have high blood pressure now, odds are that you will. More than half of people over 60 have hypertension, one of the key causes of strokes and heart attacks.
And cutting back on salt isn’t the only way to keep a lid on blood pressure.
In 1997, the Dietary Approaches to Stop Hypertension (DASH) study essentially replaced much of the saturated fat and added sugar in a typical American diet with fruits, vegetables, and low-fat dairy foods.6 With 10 servings a day of fruits and vegetables, a typical 2,000-calorie DASH diet had room for only seven (small) servings of grain.
The results were stunning: Systolic blood pressure (the higher number) fell by 5. 5 points overall after eight weeks on the DASH diet. Among those with high blood pressure, it plummeted by 11.4 points. “The DASH diet was a real breakthrough for lowering blood pressure,” says Sacks.
What’s more, the DASH diet slashed LDL (“bad”) cholesterol by more than 10 points.7 And “triglycerides didn’t go up, even though it was higher in carbs than the typical American control diet,” he adds.
In the follow-up OmniHeart Trial, Sacks and colleagues tweaked the DASH diet to replace some of its carbs (mostly the added sugars) with either extra unsaturated fat (mostly from oils) or extra protein (more than half of it from beans, nuts, seeds, and tofu).8 Each OmniHeart diet had room for only four or five small servings of grain a day (see “Safe at the Plate,” p. 6).
“The unsaturated Fat and protein diets were superior,” notes Sacks. But that’s fine-tuning, he adds. “If people could just switch to a regular DASH diet, that would make a huge difference.” (See www.nhlbi.nih.gov/hbp/prevent/h_ eating/h_eating.htm.)
Do refined grains raise blood pressure more than whole grains? DASH and OmniHeart both included whole grains, but weren’t designed to answer the question. So far, only one study—which needs to be replicated—has tried to.
Gave people three servings a day of whole-grain breads and cereals for three months, the participants had markedly lower blood pressure than those who got three servings a day of refined grains.
The drop—5 to 6 points in systolic pressure—is what you’d expect to see with drugs used to treat hypertension, say the authors, and “could result in decreases of the incidence of coronary artery disease and stroke by 15 percent and 25 percent, respectively.
3. Whole grains are healthier than refined grains.
There’s no shortage of reasons to eat whole grains instead of refined grains:
Obesity, diabetes, and heart disease. In study after study, people who eat more whole grains have a lower risk of obesity, heart disease, and diabetes than those who eat fewer whole grains.10-12
But whole-grain eaters are also less likely to smoke and more likely to exercise and eat a healthier diet.
Researchers “adjust” for those and other known differences, but it’s possible that something the researchers don’t know about whole-grain eaters lowers their risks.
“Most of the data suggests that unrefined grains are better than refined,” says Lichtenstein. “But if you look at those data, they’re mostly association studies that can’t prove cause-and-effect. So it’s not clear.”
On the other hand, by eating whole grains, you can’t lose.
“It’s important to stress whole grains because they have benefits beyond those associated with blood lipids and blood pressure,” adds Lichtenstein. For example, “their fiber creates a feeling of fullness that can help curb your appetite.”
Regularity. “The bran in whole grains is an excellent source of fiber that can help keep you regular,” says Lichtenstein. 14 “Most people don’t get enough of it.”
Vitamins & minerals. Refined grains are lower in vitamins (like B-6 and E) and minerals (like copper, magnesium, potassium, selenium, and zinc) than whole grains.
The potassium may lower blood pressure, and the magnesium may protect against diabetes. Why miss out on those and other nutrients that are stripped away in refined grains?
4. The healthiest diets don’t have much room for refined grains.
If you’re shooting for 2,000 calories a day, there’s not much room for a:
400-calorie Chocolate Chip cookie from Panera,
500-calorie muffin from Au Bon Pain or Dunkin’ Donuts,
1,000-calorie plate of Tomato Basil Spaghettini from California Pizza Kitchen, or
1,500-calorie serving of Chow Fun with Beef from P.F. Chang’s.
Pasta packs 200 calories a cup without sauce, and restaurants typically serve at least three cups. “Many people still think it’s okay to eat a huge plate of pasta,” says Kris-Etherton. “That’s not the right message anymore.”
The bottom line: “Most Americans need to be concerned about excess carbs because they’re overweight,” notes Lichtenstein. And it’s wise to spend your carbs on healthy foods.
“The message isn’t that all carbs are bad so get them down as much as you can,” explains Sacks. “The central message is to get carbs from vegetables, fruit, and whole grains rather than from sugars, fruit juice, and refined grains.”
1 www.nhlbi.nih.gov/health/dci/Diseases/ms/ms_all.html.
2 www.nhlbi.nih.gov/health/dci/Diseases/ms/ms_
whatis.html.
3 J. Clin. Invest. 119: 1322, 2009.
4 Br. J. Nutr. 104: 125, 2010.
5 Ann. Intern. Med. 142: 725, 2005.
6 N. Engl. J. Med. 336: 1117, 1997.
7 Am. J. Clin. Nutr. 74: 80, 2001.
8 JAMA 294: 2455, 2005.
9 Am. J. Clin. Nutr. 92: 733, 2010.
10 Pub. Health Rep. 11: 554, 2007.
11 Curr. Atheroscler. Rep. 12: 368, 2010.
12 Cochrane Database Syst. Rev. (1): CD006061, 2008.
13 Am. J. Clin. Nutr. 78: 83, 2003.
14 Am. J. Clin. Nutr. 88: 1256, 2008.
Step Away from the Carbs
Here’s a sampling of typical high-carb foods and a few lower-carb ones. Each serves just one person, according to the menus. If you eat 2,000 calories a day, shoot for about 80 grams of carbs from grains (preferably whole). “Carbs” in this chart include added and naturally occurring sugars, so it may be easier to count servings of grains (see “Safe at the Plate,” p. 6).
Safe at the Plate
In the OmniHeart study, two diets—one higher in unsaturated fat and one higher in protein—cut heart disease risk the most. Here’s a day’s worth of food in a hybrid of the two diets. It has roughly 2,000 calories (which may look skimpy if you typically eat more). The four servings of grains may also seem skimpy (one serving is just ½ cup of rice or pasta or 1 thin slice of bread). Grains are limited because most of OmniHeart’s carbs come from fruits, vegetables, and beans.
LUNCH & AFTERNOON SNACK. You get 3 fruit-or-vegetable servings from the grapes, sandwich fixins’, and veggies for dipping into hummus. This menu uses its “wild card” for one of two servings of fish (the tuna in the sandwich), which can help lower triglycerides. (For other wild card options, see “A Day’s Food.”)
BREAKFAST. You can polish off 2 servings of fruit (1 orange and ¼ cup of golden raisins) at breakfast. The raisins (and ¼ cup of almonds) help round out the small serving (½ cup) of cereal.
DINNER & EVENING SNACK. Dinner racks up 4 servings of vegetables from the generous serving of spinach salad (2 cups) and the broccoli (1 cup). Rule of thumb: Fill at least half your plate with veggies (or fruit). The fresh fruit (1 cup) that tops the snack’s plain yogurt adds 2 more fruit servings. Dessert is petite.
A DAY’S FOOD
VEGETABLES & FRUIT
11 servings per day
What’s 1 serving?
½ cup cooked
vegetables
½ cup raw vegetables
1 cup salad greens
1 piece fruit
½ cup fresh fruit
¼ cup dried fruit
GRAINS
4 servings per day
What’s 1 serving?
1 slice bread
½ cup cereal, pasta,
or rice
LOW-FAT DAIRY
2 servings per day
What’s 1 serving?
1 cup milk or yogurt
1½ oz. cheese
LEGUMES & NUTS
2 servings per day
What’s 1 serving?
¼ cup nuts
½ cup cooked beans
POULTRY, FISH,
& MEAT
1 serving per day
What’s 1 serving?
¼ lb. cooked
DESSERTS & SWEETS
2 servings per day
What’s 1 serving?
1 small cookie
1 tsp. sugar
OILS & FATS
2 servings per day
What’s 1 serving?
1 Tbs. oil
1 Tbs. margarine
or mayo
WILD CARD
1 serving per day of
POULTRY, FISH, & MEAT or DESSERTS & SWEETS or OILS & FATS or GRAINS
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