Pros & Cons
- Fatty food guilt-free
- Quick weight loss
- Goodbye to sweets and bread
- More calorie-restricted than you might think
Do's & Don'ts
|Weight Loss Short-term|
|Weight Loss Long-term|
|Easy to Follow|
|For Heart Health|
Scores are based on experts' reviews
You’ll lose up to 15 pounds within two weeks, and eat lots of fatty foods.
The body is an engine; carbs are the gas that makes it go. Limiting carbs makes the body turn to an alternative fuel—stored fat. So sugars and “simple starches” like potatoes, white bread, and rice are all but squeezed out; protein and fat like chicken, meat, and eggs are embraced. Fat is burned; pounds come off.
Reducing total carbs isn’t all there is to Atkins. Limiting the carbs you take in at any one time is also in the game plan. A carb-heavy meal floods the blood with glucose, too much for the cells to use or to store in the liver as glycogen. Where does it end up? As fat.
How does the Atkins Diet work?
You go through four “phases,” starting with very few carbs and eating progressively more until you get to your desired weight. Keeping carbs at bay isn’t as simple as saying No to sugar and baked potatoes. You’ll keep acceptable foods lists handy and polish your arithmetic skills. In phase 1, for example, you’re allowed 20 grams a day of “net carbs” (pull out the food list), 12 to 15 of them from “foundation vegetables” (pull out another list) high in fiber. But as for fat, you don’t even have to trim it off your steak.
Will you lose weight?
Atkins and other low-carb diets have been studied longer and harder than most other approaches, and Atkins does appear to be moderately successful, especially in the first couple of weeks. That’s only part of the story, however.
Much of the initial loss is water, say experts, because of the diet’s diuretic effect. That’s true of many other diets, too, and is one of the reasons researchers don’t judge diets based on a few weeks of results. In diet studies, long-term generally starts at two years. Here’s what several key studies had to say about Atkins and other low-carb diets:
- Over short periods, Atkins results vary. In one study, published in 2006 in the British Medical Journal, Atkins dieters lost an average of 10 pounds in the first four weeks while those on meal-replacement (Slim Fast), caloric-restriction (Weight Watchers), and low-fat (Rosemary Conley’s Eat Yourself Slim book) diets lost 6 to 7 pounds. At the one-month point and thereafter, however, there were no significant differences in weight loss among the groups.
- A 2007 study that appeared in the Journal of the American Medical Association divided roughly 300 overweight or obese women into groups and assigned them to one of four types of diets: low-carb (Atkins), low-fat (Ornish), low saturated-fat/moderate-carb (LEARN), and roughly equal parts protein, fat, and carb (Zone). At two months, the Atkins dieters had lost an average of about 9½ pounds compared with 5 to 6 pounds for those on the other three diets. At six months, weight loss for the Atkins group averaged about 13 pounds; the other three groups averaged 4½ to 7 pounds. At 12 months, the Atkins group had lost what researchers called a “modest” 10 pounds; the other dieters averaged 3½ to 6 pounds. Drawing firm conclusions from this study is risky, however. The dropout rate in all four groups was significant, and many participants didn’t follow their assigned diet. The Atkins dieters, for example, took in far more carbs than they were supposed to.
- A third study, published in 2010 in the Annals of Internal Medicine, found no clear advantage either to a low-carb diet based on Atkins or a generic low-fat diet. Both helped participants lose an average of 11 percent of their starting weight at 12 months, but they gained about a third of it back after that. At two years, average loss for both diets was 7 percent of initial body weight. (That’s still not bad—if you’re overweight, losing just 5 to 10 percent of your current weight can help stave off some diseases.) An analysis of five studies that compared low-carb and low-fat diets published in 2006 in the Archives of Internal Medicine concluded similarly—while weight loss was greater at six months for low-carb dieters, by 12 months that difference wasn’t significant.
- It is still unclear, regardless of claims made for low-carb diets, whether the main reason for weight loss is carb restriction specifically or simply cutting calories. A study published in 2009 in the New England Journal of Medicine found that after two years, participants assigned either to a 35 percent or a 65 percent carb diet lost about the same amount of weight—6 to 7½ pounds on average. In 2003, researchers who analyzed about 100 low-carb studies concluded in the Journal of the American Medical Association that weight loss on those diets was associated mostly with cutting calories and not with cutting carbs.
- Researchers reviewed 17 different studies that followed a total of 1,141 obese patients on low-carb eating plans, some similar to the Atkins diet. Results were published in 2012 in Obesity. The study shows that low-carb dieters lost an average of nearly 18 pounds over a period of six months to a year. They also saw improvements in their waist circumference.
Does it have cardiovascular benefits?
A few small, short studies suggest Atkins raises HDL cholesterol and lowers blood pressure, reducing the risk of heart attack and stroke. But many of the studies were small and short, and some of the positive findings did not carry enough statistical weight to be trustworthy. And all that fat worries most experts.
Can it prevent or control diabetes?
No good evidence suggests that Atkins accomplishes either.
Prevention: Research into Atkins or other low-carb diets is sparse. Frequent spikes and dips in blood glucose after carb-heavy meals can, according to Atkins literature, lead to insulin resistance, a frequent precursor to type 2 diabetes where the body doesn’t respond as it should to the hormone. However, diabetes experts emphasize weight gain from excessive caloric intake, regardless of where those calories come from, increases the risk of developing insulin resistance and possibly diabetes. Losing weight and keeping it off, no matter the diet, will almost certainly reduce your risk of developing the chronic disease.
Control: The New Atkins for a New You, the latest version of the diet, devotes an entire chapter to diabetes management, but cites only five very small studies to support claims that low-carb diets improve blood-sugar control. Diabetes specialists agree that because blood glucose dips and spikes are intimately tied to carb consumption, carefully choosing and restricting some carbs is important. But the 30 or fewer grams a day specified in some Atkins phases is too extreme, concluded the authors of a 2005 report published in Nutrition and Metabolism.
A few recent studies have shown that Atkins or other low-carb approaches help lower blood glucose and insulin levels—suggesting they may stave off diabetes or help diabetics control their condition—but they don’t do it significantly better than other diets.
Are there health risks?
No indications of serious short-term risks have surfaced. Reported side effects are generally minor. They include weakness, nausea, dizziness, constipation, irritability, and bad breath. Atkins hasn’t been studied beyond two years, so long-term risks are uncertain.
Most experts feel that diets high in saturated fat significantly raise the risk of heart disease and cardiovascular events such as heart attack and stroke. The latest Atkins book calls this a “myth,” however, asserting that carb restriction changes the way the body processes fat in the diet.
Keep in mind Atkins isn’t safe for everyone:
- Pregnant women should go directly to the phase 4 maintenance stage.
- Adolescents and diabetics on medications to control blood sugar should consult with their doctors.
How well does it conform to accepted dietary guidelines?
Fat. Compare the government’s recommendation in the 2010 Dietary Guidelines for Americans that 20 to 35 percent of daily calories come from fat with as high as 63 percent for Atkins.
Protein. It’s within the acceptable range for protein consumption.
Carbohydrates. Atkins does not provide the recommended amount of carbohydrates during any phase.
Salt. The majority of Americans eat too much salt. Atkins will keep you below the generally recommended daily maximum of 2,300 milligrams, but if you’re 51 or older, African-American, or have hypertension, diabetes, or chronic kidney disease, the recommended daily sodium limit is 1,500 mg., and Atkins does not meet that standard. You may be able to make substitutions to conform to a low-sodium diet.
Other key nutrients. The 2010 Dietary Guidelines call these “nutrients of concern” because many Americans get too little of one or more of them:
- Fiber. Getting the recommended daily amount—22 to 34 grams for adults—helps you feel full and promotes good digestion. Atkins initially provides less fiber than is generally recommended but reaches an acceptable amount (for most, but not all) by the last phase.
- Potassium. A sufficient amount of this important nutrient, according to the 2010 Dietary Guidelines, counters salt’s ability to raise blood pressure, decreases bone loss, and reduces the risk of developing kidney stones. It’s not that easy to get the recommended daily 4,700 mg. from food. (Bananas are high in potassium, and you’d have to eat 11 a day.) Most Americans take in far too little. Atkins falls somewhat short of the recommended amount, but probably supplies more than most people get.
- Calcium. It’s essential not only to build and maintain bones but to make blood vessels and muscles function properly. Many Americans don’t get enough. Women and anyone older than 50 should try especially hard to meet the government’s recommendation of 1,000 mg. to 1,300 mg. Good sources include low-fat dairy products and calcium-fortified juices and cereals. You should be in the ballpark on Atkins.
- Vitamin B-12. Adults should shoot for 2.4 micrograms of this nutrient, which is critical for proper cell metabolism. Most sample Atkins plans provide more than enough, but your actual intake will vary based on your meal choices. Work in fish like salmon and trout, along with yogurt and fortified cereals (if you’re allowed enough carbs, that is). They’re all good sources.
- Vitamin D. Adults who don’t get enough sunlight need to meet the government’s 15 microgram recommendation with food or a supplement to lower the risk of bone fractures. You’ll probably want to go the sun or supplement route on Atkins; sample plans show it doesn’t come close to meeting the requirement. Still, you could eat just 3 ounces of sockeye salmon, which packs about 20 micrograms of vitamin D, to satisfy the requirement. Or just try to work in low-fat dairy and fortified cereals.
Supplement recommended? Yes, a daily multivitamin with minerals, including magnesium and calcium, as well as supplemental omega-3 from fish oil and vitamin D for those who don’t get much sun. If you’re up for researching the nutrient content of different foods, you could instead make sure your diet includes plentiful amounts of ingredients rich in key nutrients.
How easy is it to follow?
How much do you love sweet and starchy foods? Would you miss crusty French bread? Pasta? Grape jelly? Diets that severely limit entire food groups for months and years tend to have lower success rates than less-restrictive diets do.
One study showed higher percentages of Atkins dieters dropping out at 3, 6, 12, and 24 months than others did on a low-fat diet, but the differences were not significant. Two other studies that included low-carb dieters concluded diet type wasn’t connected to dropout rate.
At home, building variety into meals is a little harder than usual. Eating out takes more effort. Alcohol is limited. Company products and online resources may be helpful. In 2013, Atkins launched a frozen food line, which the company says is the first low-carb frozen food line on the market.
Recipes. Atkins provides meal plans, recipes with ingredient lists, and food carb counts, all in print-friendly format. There is at least a smattering of recipes across a range of cuisines from American to Middle Eastern to French to Asian.
Eating out. Restaurants and dinners with friends are doable if you’ve read Atkins’ list of approved fast-food and cuisine-specific options before heading out (and if you’re not bashful about asking lots of questions about meal preparation).
Alcohol. If you like to kick back with a beer or a glass of wine, you might be a little cranky for the first couple of weeks, when alcohol is forbidden. (Beer and wine contain carbs, and all alcoholic beverages add calories.) You are allowed to work it back in during phase 2, to perhaps one drink a day. But even carb-free spirits will slow down fat-burning, according to Atkins.
Time-savers. When you’re in a hurry, Atkins has convenience foods available, like shakes ($7 for a four-pack), snack bars ($6 for a five-pack), penne pasta ($4 for 12 ounces), and all-purpose baking mix ($10 for 2 pounds).
Extras. On its website, Atkins offers a free meal planner, carb counter, two-week meal plan, forums, and interactive goal-setting tools.
Nutrition experts emphasize the importance of satiety, the satisfied feeling that you’ve had enough. Hunger shouldn’t be a problem on this diet. Protein and fat generally take longer than carbs to digest; the hunger center in your brain won’t be sending out “Feed me” messages two hours after a meal.
What’s not to like about juicy burgers topped with melting cheddar? Still, bun-less burgers and dips without chips could get old in the long haul.
How much does it cost?
Meat and fresh veggies are pricier than most processed and fast foods. How much more you’ll spend will depend largely on your choices of protein sources. Are you buying mostly ground beef or springing for veal? Chicken or turkey? Chuck vs. New York strip? Buying in season should keep the veggie tab reasonable.
The New Atkins for a New You, an essential guide, is $16.
Does the diet allow for restrictions and preferences?
Most people will be able to customize Atkins to their needs—choose your preference for more information.
Atkins offers sample meal plans and recipes with carb totals for both vegetarians and vegans.
If you’re a vegetarian or vegan, you’ll start out in phase 2 with extra carbs—vegetarians are allowed an added handful, while vegans get almost double the usual phase 2 amount. (That’s to get sufficient protein, in the absence of animal protein, from foods that may be more carb-heavy.) Lots of your protein will have to come from plant sources and soy products (some vegetarians will also have eggs to make things easier) and you’ll need to add some oils to ratchet up your fat intake.
No meal plans or specific recipes, but the foods that form the base of the Atkins diet—eggs, meats, and veggies—are all gluten-free. You’ll need to keep in mind that just because a product is labeled “gluten-free” doesn’t mean it doesn’t have carbs. And while Atkins shakes are gluten-free, stay away from the bars—they either contain gluten or were manufactured alongside gluten products.
Atkins doesn’t have low-sodium meal plans. Compliance will be doable but not easy. Besides restricting carbs, you’ll need to avoid or put severe limits on cheese (cottage or otherwise) and high-sodium protein sources like sausage, bacon, and canned tuna. On the flip side, you won’t be eating many high-sodium prepackaged foods—you’ll be cooking a lot—and fresh veggies are virtually sodium-free as long as you don’t reach for the shaker.
Lots of kosher recipes with carb content information on the Atkins website, but no daily menu plans.
Atkins doesn’t offer recipes or guidance.
What is the role of exercise?
Encouraged, especially by the time you reach the maintenance phase, but not required.
If you choose to exercise, Atkins recommends waiting a couple of weeks to get used to your new eating regimen, particularly if you weren’t exercising before. If you were, you might choose to keep it up—just be ready to scale back if you feel your energy dipping too low.
Atkins Nutritionals comments:
The U.S. government’s Dietary Guidelines were used to determine “nutritional completeness.” Since these guidelines focus on low-fat recommendations rather than low-carb, it’s logical that Atkins scored lower than others. Atkins is different by design and by science. The score should also consider the quality of the science supporting the diet. Sixty published, independent, peer-reviewed studies back the diet's safety and efficacy in such prestigious medical journals as the Journal of the American Medical Association, New England Journal of Medicine, and Annals of Internal Medicine. In addition, the Atkins Diet does NOT restrict vegetables. Throughout the plan, the dieter can eat more vegetables on a daily basis than is recommended by USDA guidelines. After two weeks an individual starts to add berries, nuts, seeds and yogurt; in phases three and four, legumes and whole grains can be added. Finally, we do focus on fat, but a balance of fats that are commonly agreed to be healthy, such as monounsaturated fats like olive oil and avocado. You can easily avoid almost all saturated fats on Atkins by following the plan as a vegetarian.
—Colette Heimowitz, Vice President of Nutrition and Education, Atkins Nutritionals
The editors respond: The federal government's 2010 Dietary Guidelines reflect research-based findings and are generally accepted by nutrition experts.
Last updated by Kurtis Hiatt | September 23, 2013
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