close

Privacy guaranteed - Your email is not shared with anyone.

Little Evidence to Support Low-Carbohydrate Diets

Discussion in 'Food Forum' started by theHULK9281, Apr 30, 2004.

  1. theHULK9281

    theHULK9281 Gentle Giant

    Messages:
    102
    Likes Received:
    0
    Joined:
    Feb 23, 2004
    Location:
    Steelers Country
    News Author: Laurie Barclay, MD
    Clinical Reviewer: Gary Vogin, MD
    CME Editor: Bernard M. Sklar, MD, MS

    April 8, 2003. Low-carbohydrate diets have been all the rage lately, but a systematic review published in the April 9 issue of The Journal of the American Medical Association reveals insufficient evidence to support or refute the concept thus far. The bottom line appears to be that a calorie is a calorie. The editorialist reviews the issue of adult weight loss.

    "Recently, low-carbohydrate diets have resurged in popularity as a means of rapid weight loss, yet their long-term efficacy and safety remain poorly understood," write Dena M. Bravata, MD, MS, from the Center for Primary Care and Outcomes Research in Stamford, California, and colleagues. "Our results demonstrated the marked discordance between the knowledge needed to guide dietary choices and the information that is available in the medical literature."

    Although millions of copies of three books on low-carbohydrate diets have sold in the U.S. over the past five years, the American Dietetic Association, the American Heart Association, and other professional organizations have warned the public against potentially serious medical consequences of these diets.

    The investigators searched the literature for studies of low-carbohydrate diets published between 1966 and February 2003. They identified 107 articles reporting data on 3,268 participants, of whom 663 patients received lower-carbohydrate diets (60 grams of carbohydrates per day [g/d] or less), and 71 patients received the lowest-carbohydrate diets containing 20 g/d or less of carbohydrates, which is the recommended threshold for some of the most popular diets.

    None of the studies evaluated diets of 60 g/d or less of carbohydrates in subjects with a mean age older than 53 years, and only five studies evaluated these diets for more than 90 days. Weight loss in obese patients was associated with longer diet duration (P = .002) and restriction of calorie intake (P = .03), but not with reduced carbohydrate content. Low-carbohydrate diets had no significant adverse effects on serum lipid levels, fasting serum glucose levels, fasting serum insulin levels, or blood pressure.

    "Our quantitative synthesis...on the efficacy and safety of low-carbohydrate diets suggests that there is insufficient evidence to make recommendations for or against the use of these diets," the authors write. "We found insufficient evidence to conclude that lower-carbohydrate content is independently associated with greater weight loss compared with higher-carbohydrate content.... Given the limited evidence in this review, when lower-carbohydrate diets result in weight loss, it also is likely due to the restriction of calorie intake and longer duration rather than carbohydrate intake."

    The investigators recommend additional research evaluating the long-term effects and consequences of low-carbohydrate diets in both older and younger subjects with and without diabetes, high cholesterol, and hypertension.

    None of the authors has financial or other conflicts of interest concerning low-carbohydrate diets or diet projects. No manufacturer or vendor of dietary goods or services funded this study.

    In an accompanying editorial, George A. Bray, MD, from Louisiana State University in Baton Rouge, notes that the worldwide epidemic of obesity will be followed by a worldwide epidemic of diabetes.

    "The broader issue of whether a unique diet exists that will produce long-term weight loss has yet to be evaluated," he writes. "Although the truth of 'a calorie is a calorie' has been reaffirmed by [this review], the question of whether patients can adhere more easily to one type of diet or another remains to be answered."

    JAMA. 2003; 289:1837-1850, 1853-1855
     
  2. theHULK9281

    theHULK9281 Gentle Giant

    Messages:
    102
    Likes Received:
    0
    Joined:
    Feb 23, 2004
    Location:
    Steelers Country
    Another article:

    The Lowdown On Low Carb Products
    MSN Health

    Hard-bodied men and women working out at the gym may not seem like typical beer drinkers, but that's exactly what today's carb-conscious marketing campaigns would like you to believe.

    A flood of low-carb beer, pasta, bread, candy, and even ice cream has hit supermarket shelves in recent months to fulfill the cravings of dieters who are counting carbohydrate grams rather than calories. The products promise to help Atkins and other low-carb diet devotees to, "Lose the carbs. Not the taste," according to a Michelob Ultra Low Carbohydrate Beer billboard campaign.

    But will a low-carb beer really help you lose your beer belly? Or will trading your favorite ice cream for a lower carbohydrate version make you healthier? In a word, "no," say the experts.

    "I think a lot of people think that with low-carb snacks and desserts they can do an end run around a healthy diet, but you can't," says Larry Lindner, an instructor at the school of nutrition science and policy at Tufts University in Boston. "It's not going to work in the long run, and it's certainly not going to be good for your body."

    In fact, Lindner recently compared a sampling of low-carb products with their regular counterparts and found they often contain virtually the same number of calories, despite the much higher price tag for the low-carb versions.

    For example, a 12-ounce bottle of Miller Lite has 96 calories and 3.2 grams of carbohydrates, and a bottle of Michelob Ultra Low Carbohydrate has only one less calorie and about half a gram fewer carbohydrates but costs 12% more. In comparison, regular beers typically contain about 150 calories and more than 10 grams of carbohydrates per serving.

    "When a product markets itself or is perceived as something that is useful for weight loss, and it doesn't have any fewer calories than the food it's meant to replace, from a weight-loss perspective there is no difference," say Linder. "And from a nutrition perspective a low-carb beer is not more nutritious or more healthful for you than a regular beer."

    What Does "Low Carb" Mean?

    Even though many products tout themselves as "low carb" or are marketed to "carb counters," the FDA has not legally defined what "low carb" means, as it has for low fat, low sodium, and low cholesterol.

    Experts say that until the FDA decides to weigh in on the carbohydrate issue, it's up to consumers to educate themselves on how to interpret low-carb claims on product labels.

    By law, food manufacturers are required to list the number of total carbohydrates in a product on the nutrition facts label. But makers of low-carb products often include another box next to the nutrition label that has information on the "net carb" content of the food.

    The net carbohydrate content is designed to reflect the amount of carbohydrates the product contains that will cause blood sugar levels to rise, a key factor in low-carbohydrate diets such as Atkins and the South Beach Diet.

    "There is no legal definition of net carbs. That's their math," says Lindner. "They have a formula about how the number of grams of carbs don't count the way you think they would count."

    Registered dietitian Samantha Heller says that in calculating the net carbohydrate content, many food companies subtract the number of grams of dietary fiber as well as other carbohydrates such as glycerin and sugar alcohols from the number of total carbohydrates listed in the nutrition facts label.

    "Their rationale is that the glycerin and the sugar alcohols do not raise blood sugar as quickly or as high as the regular carbohydrates," says Heller, who is a senior clinical nutritionist at New York University Medical Center. "Though this is true, they're choosing to ignore the fact that they still have calories."

    Rather than relying on the manufacturer's math, Heller recommends that carb-conscious consumers look at the total number of carbohydrates in the nutrition facts label and then subtract only the dietary fiber in order to get an idea of how many net carbohydrates are in the product.

    Unlike sugar alcohols, Heller says dietary fiber does not make a significant contribution to the calorie content of foods because it's not readily digested by the body

    What Goes in When the Carbs Go Out?

    When the sugars and starches that cause blood sugar levels to rise are taken out of foods that rely on these elements for flavor and texture, something has to take their place.

    In the case of low-carb candy, ice creams, and other sweets, that often means sugar alcohols, such as sorbitol, maltitol, and lactitol.

    "They have a very similar chemical structure as sugar, but they have alcohol attached to it, which regular sugar doesn't," says Mary Ellen Camire, PhD, a professor of food science and human nutrition at the University of Maine and a product development expert with the Institute of Food Technologists.

    "The drawback is that because they have alcohol, they're really good at attracting water," says Camire. "If you eat too much, those alcohols pull water into your gut because they're not digested and then you end up with diarrhea."

    Camire also warns that you may get the same effect from eating low-carb breads or pastas. In order to lower the carbohydrate content of these traditionally carbohydrate-rich foods, manufacturers often add extra protein or a type of highly processed starch that is hard to digest in order to add texture and bulk.

    "What happens is that you can process starch so that very little of it is digestible, and we call that 'resistant starch,'" explains Camire. "It ends up being analyzed for the food label as dietary fiber."

    "You don't want to get far from the restroom, but that's a good thing," says Camire. "The body recognizes it as fiber, and most Americans aren't getting enough fiber anyway. So it's a win-win situation, you get lower carbohydrates and more fiber."

    But by taking whole grains out and replacing them with other fillers, Heller and Camire say that low-carb dieters may also be missing out on nutritional benefits, such as the natural antioxidants and phytochemicals found in whole grains.

    It's the Calories That Matter

    Nutritionists say that America's obesity epidemic shows no signs of waning, and the low-carb craze may go the same way as the low-fat frenzy a decade ago.

    "During the low-fat craze, people ran out and bought low-fat Snackwell cookies," says Lindner. "Well, guess what? They have the same number of calories as Oreos and Chips Ahoy, and you're not going to lose weight if you keep eating those. It's the same thing with the low-carb products. They essentially have as many calories as the things they are meant to replace, and you're not going to lose weight if you don't eat fewer calories."

    Heller agrees and says winning the battle against the bulge isn't about replacing one source of empty calories, such as beer, with another lower carbohydrate version. Instead, it's about making healthy lifestyle changes.

    "You can lose weight by eating healthy food or unhealthy food," Heller tells WebMD. "We would prefer, and your body would be happier, if you were trying to reach and maintain a healthy weight by eating healthy food."

    "A low-carb approach is not the answer to a healthy diet," says Heller.
     

  3. mzenzer

    mzenzer Argus-eyed

    Messages:
    657
    Likes Received:
    0
    Joined:
    Feb 14, 2002
    Location:
    Louisiana



    Yeah, and these groups have long been proponents of the low-fat, high-carb diets. They are protecting their own flawed ideas.

    I don't trust pre-packacked low carb products, as I eat as much natural stuff as possible. However I can vouch that low carb diets do work. Due to a back problem and very poor metabolism, I've had to lose weight several times in the last decade or so. Early on, I did the low-fat, high carb thing, but I was very athletic. It was hard work. The last two times, I did a modified atkins diet and lost the weight I needed with little to no exercise. Atkins, in my opinion, if followed to the letter is unhealthy. And yes, I've read the book (several times) and still use my well worn copy for reference. I am currently doing the South Beach Diet. The principles are the same as Atkins and sugar busters, but south beach is much healthier in that the meat you do eat is lean, and it is easier to do. Much more carbs are included, but they are the right ones, not the heavy sugar producing ones. I hardly feel like I'm dieting and I've lost my first 6 pounds in one week.

    No diet, even low fat, is good for a lifetime without any ill effects. I mean, our body's need fat too. And if the uninformed dieters keep their fat intake very low, they are doing just as much damage as unabated eating. Good fats actually fight the bad fats, so to speak. There have been many cases of people doing the Atkins diet and their cholesterol actually lowered to healthy levels. However, these were usually the ones that included meats with the good fats such as salmon, or low fats such as chicken, and cooked with healthy oils and ate nuts.

    It's all about balance. If we stayed away from processed crap as much as possible, ate more fiber and vegetable based carbs and less starch, white breads, and to some degree red meats, we'd all live a lot longer.
     
  4. theHULK9281

    theHULK9281 Gentle Giant

    Messages:
    102
    Likes Received:
    0
    Joined:
    Feb 23, 2004
    Location:
    Steelers Country
    Yes, I concur that balance is paramount. I just hate it when people say carbs are bad :rolleyes:. The reason why people think carbs are so bad is because they're not eating the right kind. I think everybody needs to get to know the glycemic index (GI).

    What's the glycemic index people ask? Well, the glycemic index is a way to measures how fast a carbohydrate triggers a rise in circulating blood sugar. The higher the GI of a carb, the more insulin is secreated into the blood stream causing a more likely of a chance that the carbs get stored as adipose tissue (fat).

    That being said, weight gain is mostly about calories in vs. calories out. Meaning if you burn more calories than you consume, your going to lose weight. If you consume more calories than you burn, your going to gain weight.....it's that simple, but I know 99% of people are not going to count thier calories throughout the day....

    *rant off*
     
  5. theHULK9281

    theHULK9281 Gentle Giant

    Messages:
    102
    Likes Received:
    0
    Joined:
    Feb 23, 2004
    Location:
    Steelers Country
  6. mzenzer

    mzenzer Argus-eyed

    Messages:
    657
    Likes Received:
    0
    Joined:
    Feb 14, 2002
    Location:
    Louisiana


    I agree 100%. I'm not a low-carb proponent nor a low-fat proponent. Like you said, people aren't eating the right kind of carbs.

    The GI is the most helpful dieting/health tool I recommend to people. So many people want a quick fix and never want to invest time in reading a little on nutrition, that they take whatever the latest diet fad is, read a fraction of info on the diet and run with it, usually with marginal results. But I've given people GI lists and it's easy for them to undertand and follow.
     
  7. theHULK9281

    theHULK9281 Gentle Giant

    Messages:
    102
    Likes Received:
    0
    Joined:
    Feb 23, 2004
    Location:
    Steelers Country
    Well, I'm glad someone actually cares about what they put into their body and has actually taken the time to research. Kudos to you. Now, if everybody else had the same ambition, obesity wouldn't be a major problem in today's society.
     
  8. MB-G26

    MB-G26 Non-existent STUPID GURL Lifetime Member

    Messages:
    7,734
    Likes Received:
    1,692
    Joined:
    Oct 9, 2001
    Location:
    Missing Sharon
    I haven't read any of 'the diets' and am not on a "diet", but would like to know just for general snacking guidance - which are the items in the list to avoid (examples or criteria) and which are the "good" ones?
    m
     
  9. theHULK9281

    theHULK9281 Gentle Giant

    Messages:
    102
    Likes Received:
    0
    Joined:
    Feb 23, 2004
    Location:
    Steelers Country
    Some of the common carb foods that are good to eat.....

    All-bran cereal
    Special K
    Oatmeal (rolled oats)
    Brown rice
    Vegetables (any green leafy ones)
    Apples
    Carrots
    Chick peas
    Grapes
    Green peas
    Kidney beans
    Black beans
    Nopal
    Oranges
    Peaches
    Peanuts
    Pears
    Pinto beans
    lentils
    Strawberries
    Sweet corn
    Barley
    Hominy
    Split peas
    Rye
    Beets
    Cantaloupe
    Pineapple
    Apple juice
    Bananas
    Buckwheat
    Fettucine
    Navy beans
    Parboiled rice
    Pearled barley
    Sourdough wheat bread
    Spaghetti
    New potatoes
    Sweet potatoes
    Wild rice
    Chana dal
    Cherries
    Soy beans
    Pita bread
    Plums
    Grapefruit
    Apricot
    Skim milk
    Vermicelli

    I didn't list all of them, but these are the more common ones. I'm not going to make a bad list because if it's not on this list I just provided, most likely it's not a good choice.
     
  10. Captain Caveman

    Captain Caveman a.k.a. DaReaper

    Messages:
    1,251
    Likes Received:
    0
    Joined:
    Apr 12, 2003
    Location:
    Colorado
    Thanks for posting the GI. I tried a modified Atkins routine last year and lost almost 40lbs in 4mo. I felt great, was sleeping better, had lower cholesterol and blood presure and, well this is a little personal so lets just say my wife was alot happier. About that time is when the low-carb craze really hit. Almost over night you could go to the grocery store and get low-carb bread, pasta you name it off the shelf with the unspoken message of "don't worry, we've taken all the guess work out of it, just trust us". I've been trying these items for a few months now and guess what, I gained almost all the weight back. So I'm going back to my original way and going to take the carbs up slowly until I find the level my body can metabolize carbs and this time go with more lean meats.

    On a side note...I've tried the high carb-low fat thing and my body just can not adapt to it. With my metabolism I need to watch my carbs more than anything else. Everybody is different, and I just love it when a doctor tells me that if I don't eat less meat more low fat foods and do what he/she tells me to do or I will die I just laugh. No, low carb isn't for everybody but neither is low fat.

    Bottom line, do what works for you and stick with it. Get on a moderate Exercise routine. And for God's sake stay away from the fast foods and soda. I think fast food and soda are the major contributors to the ever increasing waist line of America. Well that and inactivity.
     
  11. darin2

    darin2

    Messages:
    348
    Likes Received:
    0
    Joined:
    Apr 14, 2001
    Location:
    Georgia


    I just find it funny that the title of your post is "little evidence to support low-carbohydrate diets". You then site a year old study that states clearly in the first paragraph, "insufficient evidence to support or refute the concept thus far". I've seen plenty of people bend this study to say low carb doesn't work...but it also states, that it can't refute it either. Just taking a little too much out of context for me.
     
  12. lethal tupperwa

    lethal tupperwa

    Messages:
    9,467
    Likes Received:
    1,619
    Joined:
    Aug 20, 2002
    Location:
    Virginia
    The promos look good the food looked tasty -next week on the food chanel.

    Billed as the lo-carb chef.