|Michigan → Ross → samoore → Personal|
|Nutrition educational information|
|Dr. Scott Moore||April 2012|
This page contains many links that I have found useful over the years as I have increased my understanding of nutrition and health. (BTW, I am a professor in a business school and have no formal education in nutrition or health — I am just a guy trying to stay healthy.) I try to keep this updated as new items cross my virtual desk. When reading these posts, the most important thing to keep in mind is that you should be skeptical. You should read all of this with a doubting mind, not looking to confirm or disconfirm any pre-existing beliefs, but looking for evidence gathered carefully.
- This is a video of a presentation by the guy who did “Fat Head”. It is just over an hour (5 parts, hosted on YouTube). I highly highly recommend that you take some time to watch this before it is taken down. His explanation at the beginning of the different types of scientific investigations (and their relative worth) would make watching the whole thing worthwhile, but then he piles on at the end with a really great description of the relationship between eating and getting fat (it’s not what you think!!!). In between he also touches on cholesterol and heart disease.
Take the time; I bet it will have a huge effect on your thinking.
- This article, titled “Is red meat killing us?”, by Dr. Peter Attia serves a couple of purposes. Primarily, it is a deconstruction of the horrible papers that pass for “nutrition science”. It also points out why a study released in early 2012 indicting red meat should not have any attention paid to it.
- Fantastic description of research that shows almost all medical/nutritional research is faulty. It’s in the November 2010 Atlantic, and it’s a hugely entertaining and informative read.
Basic Dietary advice/ Low Carb
The anti-“Supersize Me”: Fat Head
- Have you ever seen the movie Supersize Me? It’s a movie by Morgan Spurlock that purported to show how fat a person becomes if he/she only eats fast food. There’s a movie called Fat Head that presents related ideas about this movie (it’s basically a counterpoint). (It’s also funny and the kids enjoyed it, too.)
You might notice that my Amazon review of it is still the #3 review. It’s the only movie I’ve ever reviewed.
- This is a promo of the movie put together by some students at Western Illinois University.
- Here are several trailers/outtakes of the movie. These actually make up a maybe a quarter of the movie, but you can get a good idea of what it’s like, and whether you’d like to watch the whole thing.
Videos on diet and health
Some more of my favorite videos (not from the movie):
- Cholesterol & Heart Disease (Dr. Malcolm Kendrick) (2 minutes)
- The Skinny on Obesity: this is the first of seven episodes on eating in a healthy manner.
- Sugar: The Bitter Truth by Dr. Robert Lustig (1.5 hours)
- Why are thin people not fat?: This is a 7-part series from the BBC (a bit over an hour) that reports on an overeating experiment in which some people do not gain nearly as much weight as would be the case if the body worked in the way predicted by the “calorie is a calorie” crowd. (Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7)
- Speech by Gary Taubes (1.5 hours)
- Gary Taubes interview (15 minutes)
- How Dr. Terry Wahls cured her MS with proper eating
- Research findings (from Dr. Stephen Phinney) behind low carb eating
- Dr. Mary Vernon describes how low carb eating improves our health (and weight)
- Really informative, scientific, evidence-based lecture to the Oregon Cattleman’s Association in which he’s talking to farmers who raise cattle and what they can do to get the word out that the food they produce is healthy: Part 1, Part 2, background.
- Here is a series of videos with Gary Taubes and Dr. Thomas Dayspring in which they discuss carbohydrate restriction and many other topics.
- Leptin: Fat loss for smart people (by Sean Croxton; The Dark Side of Fat Loss)
If you watch these videos, you’ll get a pretty good idea of why I eat low carb.
Vegetarians or meat-eaters
How carbs and sugar affect our eating habits
Analyzing dietary guidelines for Americans
- A very well-respected journal, Nutrition, just published an article by some quite senior researchers in the field of nutrition that criticizes the recently released dietary guidelines for Americans. Given what it says and the quality of the journal, it should (fingers crossed) receive (but probably won’t) some major play in the media. We’ll see.
- In this video, several nutrition experts critique the 2010 USDA Dietary Guidelines.
- Tom Naughton, producer and star of Fat Head, gives a 20 minute talk at the Office of Research Integrity conference about how bad nutrition research is doing damage to the nation’s health. This is quick, focused, and to-the-point.
- Tom Naughton reports on a story of a person who ate the recommended diet but still got bad results.
- This is a different type of article, one that only this guy (Jimmy Moore) could write. He knows everyone in the low carb/fitness/nutrition worlds. And he asked many of them to reply to a question about the importance of insulin in our health and in weight loss efforts. The range of answers is stunning: some focus on physics, some on the biology, some are for your every-day mom trying to lose weight, some are for those who are focused on fitness. There is something in here for everyone. I learned a lot from it.
- Dr. Attia explains how insulin affects our body.
- Jimmy Moore conducts one of his by-now famous n=1 experiments on himself in which he eats a sweet potato with his meal under varying circumstances and preparations for a week and reports on its effect on his blood sugar. This is really remarkable information. This is the best way possible for each of us to figure out which particular foods affect our own body in detrimental (or not) ways.
Cholesterol (and fat and carbs)
- “You Bet Your Life: An Epilogue to the Cholesterol Story” by Dr. Michael Eades A great story about how we have ended up where we are today with our U.S. dietary guidelines.
- “Low-carbohydrate diets increase LDL: debunking the myth” by Dr. Michael Eades I learned a lot from this post. At this point in my education, it’s not often that I can say that. It has some really surprising information.
- “Understanding cholesterol” by Charles Washington: A nice short discussion of the relationship among carbs & cholesterol
- Dr. Attia writes a series of posts on the science of cholesterol and why it’s so important to our bodies: Part 1.
- “Truth versus hype in the Jupiter study” by Dr. Michael Eades: cholesterol, statins, nutrition research, and the media. This post is very informative about the above topics. Highly recommended. And, if you have time, the comments contain a few gems as well.
- “Diet and disease: Not what you think” by Fallon and Enig — discusses much of the evidence that shows that cholesterol does not cause heart disease.
- “The great cholesterol myth” by Malcolm Kendrick — a great debunking of the link between cholesterol and heart disease.
- “What is bad fat is actually good for you?” by Nina Teicholz — The lead from the story is “For decades, Americans have been told that saturated fat clogs arteries and causes heart disease. But there's just one problem: No one’s ever proved it.”
- “Jimmy and MONICA: A Tale From the Heart” by Tom Naughton: heart attacks, cholesterol, and diet. A really great read...
- “Recent review on statins ignores body of evidence that suggests these drugs don’t work through cholesterol-reduction”. A very in-depth review of the science on the relationship among statins, cholesterol, and heart attacks.
- “‘Super-Sticky’ Cholesterol and Diabetics” by Tom Naughton
- “Rapid health improvements with a Paleolithic diet” by Dr. Michael Eades: great article on Paleo/low carb diet, research, cholesterol. Enjoy!
- “Baboon business” by Dr. Michael Eades: discussion of a research paper on cholesterol. An absolutely fantastic analysis of a published research paper about cholesterol.
- It’s carbs that clog up your arteries, not fat (saturated or otherwise). You might consider asking your doctor for a CT heart scan (to look for calcium deposits in your arteries; this is not a CT angiogram). This is the best test for potential heart attacks. The test is cheap (your insurance might pay for it) and non-invasive. And it can really tell you what your risk of a heart attack is.
- And, as for statins and cholesterol, you should read:
- A story of how a 63-year-old man radically improved his heart health.
- Dr. Davis explains why small LDL particles are the #1 cause of heart disease in the US.
A cholesterol level of 160 is bad because it is too low. You are at much greater risk of alzheimer’s and cancer than if you were back up in the 200-300 range (where you would naturally be without drugs). Really, you should get off the statins and eat meat and egg (especially the yolks) so that your body can get back to its natural level of cholesterol. Every single cell in your body can make cholesterol — why should we ever think that it’s bad for us? It makes me crazy.
Sorry for all of this, but I worry about you folks and all these stupid doctors out there (including mine). You are not destined to have heart problems if you eat right.
- Subject: The benefits of eating grains?: From this article, evidence is discussed that would lead one to conclude that grains cause or aggravate celiac disease, arthritis, multiple sclerosis, epilepsy, and schizophrenia.
- Subject: A really solid write-up about wheat: A really solid bit of research exposing the weight gain that comes from wheat consumption.
- Subject: Two studies on gluten free diets: Nice short write-up about recent research.
- Subject: An informative interview with an author about his book about the health issues with wheat consumption: Part 1, Part 2
- Subject: really informative, quite long article on low carb, problems with wheat: Post, Short follow-up. This is one of my favorite bloggers. He only writes about 3-4 times per year as far as I can tell, but it’s always well thought-out.
- Subject: detrimental effects of fructose. A study showing the detrimental effects of fructose (vs glucose) done at Cal-Berkeley. I have lots more where this comes from related to fructose/fruits.
- Fruit and diabetes
- Subject: Nice article about salt.
- Nostrums: Cutting Salt Has Little Effect on Heart Risk. Cutting down on salt may lower blood pressure, but there is no evidence that it leads to fewer deaths or reduces the risk of heart attack or stroke in the long run, according to a new report.
How to start eating low carb
This is a pair of posts by Dr. Eades, who has written a low carb book and has supervised hundreds if not thousands of patients on this diet: Part 1, Part 2.
Typical media coverage of typically bad nutrition reports plus rebuttals
- In March 2012 news reports appeared all over the place warning of the dangers of red meat. This was typical bad nutrition “science” but you would never know it by the typically breathless reporting done by the media. The low carb community, however, did a fairly quick take-down of the “meat” (ha!) of the report:
- This article, titled “Is red meat killing us?”, by Dr. Peter Attia serves a couple of purposes. Primarily, it is a deconstruction of the horrible papers that pass for “nutrition science”. It also points out why a study released in early 2012 indicting red meat should not have any attention paid to it.
- Last gasp of the dark ages of nutrition
- Subject: the media, carbs, and fats: He examines a recent news story on ABC about the effects of eating a meal high in saturated fats on a person’s body. Be sure to watch the video (on the page) before you read the story. Note your thoughts about the story, and then read how Dr. Eades approaches the story. Very educational.
- Subject: A Fat Head primer on how to read a news story. Very interesting with some insight into the recent salt-related FDA action.
- Subject: Recent study concerning “low carb” and “meat eaters” that is about neither. A recent study about low carb meat eaters basically says that these folks (that would be me) are going to die soon. Here’s an analysis of this study that shows that this is a misrepresentation of the underlying data. In short, the low carb eaters actually weren’t eating anything that looked like low carb (a minimum of 37% from carbs!!) and, in some instances, the “vegetarian” eaters were getting more calories from meat than the “meat eaters.” What?!
- Subject: great analysis of nutritional advice in a popular press article. So funny, so informative, so sad.
- A really nice article by Dr. Michael Eades (author of Protein Power) about how mis-information and misconceptions about low carb eating is spread by the media in an off-hand way.
- Subject: medicines and how they keep us from being healthy
- Subject: Great article about recent news related to eggs. Read about some more bad science.
- Dr. Eades roots out more anti-low-carb bias in media reports about recent research findings.
Fair media coverage of Paleo nutrition and lifestyle
A really good piece on Nightline (6 minutes). The nutritionists in the middle got it wrong (of course) but everything else was good:
- Lots of meat (with all of the fat)
- Green vegetables
- No grains or rice
- Lift heavy weights and bodyweight exercises
- No pure “cardio” exercise
DeVany and Robb Wolf are real good authors to start with related to this topic.
Read these first
- Why we get fat by Gary Taubes: This is a really nice summary of a great book on why we get fat; highly recommended (both the article and the book).
- The art and science of low carbohydrate living by Jeff Volek and Stephen Phinney: Dr. Eades reviews this book and calls it “the best low carb book in print,” which is pretty high praise (especially considering he has his own book, listed below).
- The Great Cholesterol Con by Kendrick: This amazingly informative book about cholesterol is also absolutely hilarious. As the title suggests, this book focuses on disproving everything that you have been taught about cholesterol.
These books should be next
- Protein Power by Eades: describes in great detail (but in highly accessible language) why people should concentrate on eating a sufficient amount of protein and fat and should minimize the amount of carbohydrates they eat.
- Good Calories, Bad Calories by Gary Taubes: this masterwork describes just about everything we know about nutrition and why it contradicts everything we thought we knew about nutrition. He concentrates his efforts on cholesterol and fat though he touches on many other subjects. This is an amazing book, and one that will reward your efforts at completing it.
Personal success stories
The following are simply personal success stories written by people who have adopted low carb living and improved their lives as a result.
- Mark Sisson, at Mark's Daily Apple, maintains a list of success stories sent in by his readers.
- Heart-health related success stories from The Heart Scan Blog: 1
- From the Protein Power blog by Dr. Eades: 1
Curing health problems with diet
If you want to gain an entre into what scientific evidence actually says by reading abstracts and seeing pointers to the actual studies, then you should read the posts at Healthy Diets and Science.
Essentially all of the readings about low carb eating could be seen as addressing the problem of the body’s difficulty in dealing with a high load of carbohydrates. However, the following addresses the relationship between a low carb diet and diabetes directly.
The issue of Crohn’s Disease is fairly typical in modern culture. It is a fairly wide-spread problem; doctors don’t know how to treat it; medicines are prescribed but they don’t work or have side-effects. And then a low-carb approach is tried and the results are positive, very quick, cheap, and easily achieved.
Here is an article by Gary Taubes, a science journalist/health researcher whose work I highly value and respect. Note as you’re reading this: He’s writing this as a guest on someone else’s (Tim Ferriss’s) blog. It was supposed to be a chapter in Taubes’s master work, Good Calories Bad Calories, but it was cut out simply because it contributed to making the book too long.
While I highly recommend that you read this article, a short version of the take-aways is as follows:
- Reducing red meat is the old method of treating the condition but is no longer supported by research.
- Gout is an indicator that you’re becoming more insulin resistant and, hence, moving closer to having Type 2 diabetes. This is serious.
- Gout is caused by excess uric acid in the blood, and uric acid levels in the blood are raised by eating fructose.
- You should cut carbs but, more specifically, you should cut all fructose out of your diet — of course, this means fruit and anything containing high fructose corn syrup. And, since table sugar is half fructose and honey is 40% fructose, you should cut out those as well.
This article isn’t the final word, but if what you’re trying hasn’t worked so far, then trying this wouldn’t hurt.
Miscellaneous: Vitamin D/sun exposure, Nitrates/nitrites, Lap Band Surgery, Soy
- Book review and commentary about vitamin D deficiencies. Good introduction to the topic. Personally, I take 5g of vitamin D gel caps every day — 20g if and when I start to feel sick. (Here is another review by Dr. Eades.)
- Bacon & hot dogs, why worry? If you said because of the nitrates and nitrites, then you should read this absolutely amazing article. This blew my mind. Is anything that I used to know about food true?
- Gastric bypass and lap band surgery. This isn’t a pretty picture...
- Here are three articles by Kaalya Daniel about the dangers of soy — “Soy Hidden Health Dangers”, “Soy to the World”, “Recovering from Soy”. She has many more good articles on her blog, but these are a good start.
My thoughts on ketosis
There’s two ways to think about ketosis, one biological and the other evolutionary. I’ll try to cover both. I hope this helps.
I’m going to get my source material from “Good Calories, Bad Calories” by Gary Taubes, an amazing book on the history of nutritional science.
“Though glucose is a primary fuel for the brain, it is not, however, the only fuel, and dietary carbohydrates are not the only source of that glucose. If the diet includes less than 130 grams of carbohydrates, the liver increases its synthesis of molecules called ketone bodies, and these supply the necessary fuel for the brain and central nervous system. If the diet includes no carbohydrates at all, ketone bodies supply three-quarters of the energy to the brain. The rest comes from glucose synthesized from the amino acids in protein [gluconeogenesis], either from the diet or from the breakdown of muscle, and from a compound called glycerol that is released when triglycerides in the fat tissue are broken down into their component fatty acids. In these cases, the body is technically in a state called ketosis, and the diet is often referred to as a ketogenic diet. Whether the diet is ketogenic or anti-ketogenic -- representing a difference of a few tens of grams of carbohydrates each day -- might influence the response to the diet, complicating the question of whether carbohydrates are responsible for some effect or whether there is another explanation. (Ketosis is often incorrectly described by nutritionists as “pathological.” This confuses ketosis with the ketoacidosis of uncontrolled diabetes. The former is a normal condition; the latter is not. The ketone-body level in diabetic ketoacidosis typically exceeds 200 mg/dl, compared with the 5 mg/dl ketone levels that are typically experienced after an overnight fast -- twelve hours after dinner and before eating breakfast -- and the 5-20 mg/dl ketone levels of a severely carbohydrate-restricted diet with only 5-10 percent carbohydrates.)”
My goal is to be in ketosis at all times. I want my body to preferentially burn fat for energy instead of glucose. If it’s always burning fat for energy, then that should reduce my ability to store fat and reduce the stores of fat in my body.
Humans have been evolving for, give or take, 2.5 million years. We have had agriculture for, give or take, 10,000 years. That’s less than 1/2 of 1% of our time on earth. Our ancestors, for 99.5% of our existence, ate meat (wild game, fish), a few berries, and leafy plants. And on the animals the organs and fatty meat were the preferred meals. So whenever I hear some nutrition “fact” that says that eating protein or fat is somehow bad for me, I do some more research and try to understand the biological basis of the “fact” or the quality of the research supporting the “fact”. And, so far, I have yet to hear anything that convinces me that our bodies prefer something (carbs) that we have only had at our disposal to any significant degree over the last 0.5% of our existence.
My thoughts on energy level
Someone asked me this question: “My last question is how do you keep your energy level up with the little amount of carbs you eat since we derive most quick available energy from carbs and by burning fat. There doesn’t seem to be anything left for energy except protein — so doesn’t that mean that muscle is getting broken down for energy?”
Okay, a couple of different types of answers, personal and semi-biological.
Personal: When you first go “low-carb”, the first 10 days or so you will have the “low carb flu”. This is a distinct lack of energy and general all-around blah feeling. Once you get over that, everything is fine. I’ve lifted weights for 90 minutes and haven’t had any difficulty with energy, and that’s good enough for me. Also, if I’m doing serious exercise (usually lifting) for any period of time, I make sure I have had some protein right before hand so that any protein that is broken down is from my diet and not from my muscles. We generally don’t need “quick energy” for very long; usually a body in ketosis has the ability to keep up with the energy needs just fine. If I were a high school athlete, I might have some berries along with my protein shake before I work out or practice (and then the same thing afterwards).
Here’s my close-but-probably-not-quite-right biological description: When you first go low carb, your body has to take some time to switch over from primarily-carb-processing enzymes to primarily-fat-processing enzymes. This takes some time. In the meantime, your body has trouble generating enough energy to make it through the day. Once you get through this, you will operate just fine in ketosis. Your body has some glucose stored in the muscles and in the liver. That’s available for your energy needs. Your body also has a lot of triglycerides floating around (which has glycerol in it). Protein can also be used (by the liver) to create glucose by the process called gluconeogenesis. If you have eaten protein recently, then your body will use that protein for energy instead of going to your muscles and breaking them down.
Again, I’d highly recommend “Good Calories, Bad Calories”. Part III and especially Chapters 21-22 are all about this question.
My thoughts on eating guidelines for young athletes
So, since you didn’t ask, I thought I’d give you my simple eating guidelines for high school athletes.
- Stage I
- This stage will clean you up and get you used to thinking about what you eat.
- You can’t eat anything that has any trans-fat or high fructose corn syrup (HFCS). An easy way to implement this is to change this rule to “don’t eat anything can comes in a box or wrapper.”
- You shouldn’t eat anything that has poly-unsaturated fat in it or that is cooked in PUFAs. This is basically any vegetable oil. Bad bad bad. Our bodies did not evolve with the ability to process this type of oil.
- Every day have a multi-vitamin, 3 fish-oil tablets (for protection against myriad illnesses and maladies, especially heart conditions), and 2-4g of vitamin D.
- Stage II
- If they are not able to do the above, then they shouldn’t try the following. If they can do the above for a month, then it’s time to tackle these:
- Never drink any calories -- no milk, no fruit juice, no Gatorade, no Coke, nothing. Acceptable drinks are water (and more water), coffee, tea (black or green), and diet sodas. ... Okay, now prepare for a contradiction...
- Learn to drink a protein shake (with minimal carbs) right before and right after working out.
- Stop eating cereal at breakfast. Have some protein/fat combination, such as bacon and eggs.
- Nuts, cheese, and beef jerky are really good snacks. You don’t need any more than a small handful.
- Stage III
- Same thing...if they can’t do the above, then don’t try the rest. But if they can do the above, then have a go at the following:
- No pizza crust, pasta, bread, potatoes, rice, or corn.
- You can eat as much meat as you like --- bacon, hamburgers, steak, chicken (with the skin!), fish.
- You can eat as many eggs as you want. Cook them in bacon grease if you want. (I do!)
- Butter and lard are your friends. Use them to cook as much as you want.
- You can have as many green leafy veggies as you like.
- Chocolate with >= 80% cocoa will taste really good, and actually sweet, after you stop eating sweets for a while.
- No sugar; no honey. In anything. Ever.
- Berries are a very acceptable fruit. You can have 1/2-3/4 cup every day, no problem.
- Very little fruit. Maybe 1/4 banana or 1/4 apple per week. It’s nature’s dessert, and there’s no need to overindulge.
Some “academic” research related to the Atkins Diet
Lindsey is doing research for her Practical Nutrition class related to a couple of diets, one of which is the Atkins Diet. As the ever-helpful father, I said that I would volunteer to help her find a couple of journal articles that reported on fairly well done research related to this diet over the last 10 years or so. The following is what I gathered in a 30 minute period from Google and Google Scholar. I have included the results and conclusions from these studies as well as URLs so that you can read them yourself if you are so motivated. Enjoy!
- “Comparison of the Atkins, Ornish, Weight Watchers, and Zone Diets for Weight Loss and Heart Disease Risk Reduction”, by MichaelL.Dansinger, MD; Joi Augustin Gleason, MS, RD; John L. Griffith, PhD; Harry P. Selker, MD, MSPH; Ernst J.Schaefer, MD. JAMA. 2005;293:43-53.
Results: Assuming no change from baseline for participants who discontinued the study, mean (SD) weight loss at 1 year was 2.1 (4.8) kg for Atkins (21 [53%] of 40 participants completed, P = .009), 3.2 (6.0) kg for Zone (26 [65%] of 40 completed, P = .002), 3.0 (4.9) kg for Weight Watchers (26 [65%] of 40 completed, P < .001), and 3.3 (7.3) kg for Ornish (20 [50%] of 40 completed, P = .007). Greater effects were observed in study completers. Each diet significantly reduced the low-density lipoprotein/high-density lipoprotein (HDL) cholesterol ratio by approximately 10% (all P<.05), with no significant effects on blood pressure or glucose at 1 year. Amount of weight loss was associated with self-reported dietary adherence level (r = 0.60; P<.001) but not with diet type (r = 0.07; P = .40). For each diet, decreasing levels of total/HDL cholesterol, C-reactive protein, and insulin were significantly associated with weight loss (mean r = 0.36, 0.37, and 0.39, respectively) with no significant difference between diets (P = .48, P = .57, P = .31, respectively).
Conclusions: Each popular diet modestly reduced body weight and several cardiac risk factors at 1 year. Overall dietary adherence rates were low, although increased adherence was associated with greater weight loss and cardiac risk factor reductions for each diet group.
- “Efficacy of the Atkins diet as therapy for intractable epilepsy”, by Eric H. Kossoff, MD, Gregory L. Krauss, MD, Jane R. McGrogan, RD and John M. Freeman, MD, Neurology, December 23, 2003 vol. 61 no. 12 1789-1791.
Abstract: The ketogenic diet is effective for treating seizures in children with epilepsy. The Atkins diet can also induce a ketotic state, but has fewer protein and caloric restrictions, and has been used safely by millions of people worldwide for weight reduction. Six patients, aged 7 to 52 years, were started on the Atkins diet for the treatment of intractable focal and multifocal epilepsy. Five patients maintained moderate to large ketosis for periods of 6 weeks to 24 months; three patients had seizure reduction and were able to reduce antiepileptic medications. This provides preliminary evidence that the Atkins diet may have a role as therapy for patients with medically resistant epilepsy.
- “A Randomized Trial of a Low-Carbohydrate Diet for Obesity”, by Gary D. Foster, Ph.D., et al. N Engl J Med 2003; 348:2082-2090, May 22, 2003.
Results: Subjects on the low-carbohydrate diet had lost more weight than subjects on the conventional diet at 3 months (mean [±SD], –6.8±5.0 vs. –2.7±3.7 percent of body weight; P=0.001) and 6 months (–7.0±6.5 vs. –3.2±5.6 percent of body weight, P=0.02), but the difference at 12 months was not significant (–4.4±6.7 vs. –2.5±6.3 percent of body weight, P=0.26). After three months, no significant differences were found between the groups in total or low-density lipoprotein cholesterol concentrations. The increase in high-density lipoprotein cholesterol concentrations and the decrease in triglyceride concentrations were greater among subjects on the low-carbohydrate diet than among those on the conventional diet throughout most of the study. Both diets significantly decreased diastolic blood pressure and the insulin response to an oral glucose load.
Conclusions: The low-carbohydrate diet produced a greater weight loss (absolute difference, approximately 4 percent) than did the conventional diet for the first six months, but the differences were not significant at one year. The low-carbohydrate diet was associated with a greater improvement in some risk factors for coronary heart disease. Adherence was poor and attrition was high in both groups. Longer and larger studies are required to determine the long-term safety and efficacy of low-carbohydrate, high-protein, high-fat diets.
- “Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women”, by Christopher D. Gardner, PhD; et al. JAMA. 2007; 297:969-977.
Results: Weight loss was greater for women in the Atkins diet group compared with the other diet groups at 12 months, and mean 12-month weight loss was significantly different between the Atkins and Zone diets (P<.05). Mean 12-month weight loss was as follows: Atkins, –4.7 kg (95% confidence interval [CI], –6.3 to –3.1 kg), Zone, –1.6 kg (95% CI, –2.8 to –0.4 kg), LEARN, –2.6 kg (–3.8 to –1.3 kg), and Ornish, –2.2 kg (–3.6 to –0.8 kg). Weight loss was not statistically different among the Zone, LEARN, and Ornish groups. At 12 months, secondary outcomes for the Atkins group were comparable with or more favorable than the other diet groups.
Conclusions: In this study, premenopausal overweight and obese women assigned to follow the Atkins diet, which had the lowest carbohydrate intake, lost more weight and experienced more favorable overall metabolic effects at 12 months than women assigned to follow the Zone, Ornish, or LEARN diets. While questions remain about long-term effects and mechanisms, a low-carbohydrate, high-protein, high-fat diet may be considered a feasible alternative recommendation for weight loss.
- “A Low-Carbohydrate, Ketogenic Diet versus a Low-Fat Diet To Treat Obesity and Hyperlipidemia: A Randomized, Controlled Trial”, by William S. Yancy, Jr., MD, MHS, et al. Annals of Internal Medicine, May 18, 2004. vol. 140 no. 10, 769-777.
Results: A greater proportion of the low-carbohydrate diet group than the low-fat diet group completed the study (76% vs. 57%; P = 0.02). At 24 weeks, weight loss was greater in the low-carbohydrate diet group than in the low-fat diet group (mean change, −12.9% vs. −6.7%; P < 0.001). Patients in both groups lost substantially more fat mass (change, −9.4 kg with the low-carbohydrate diet vs. −4.8 kg with the low-fat diet) than fat-free mass (change, −3.3 kg vs. −2.4 kg, respectively). Compared with recipients of the low-fat diet, recipients of the low-carbohydrate diet had greater decreases in serum triglyceride levels (change, −0.84 mmol/L vs. −0.31 mmol/L [−74.2 mg/dL vs. −27.9 mg/dL]; P = 0.004) and greater increases in high-density lipoprotein cholesterol levels (0.14 mmol/L vs. −0.04 mmol/L [5.5 mg/dL vs. −1.6 mg/dL]; P < 0.001). Changes in low-density lipoprotein cholesterol level did not differ statistically (0.04 mmol/L [1.6 mg/dL] with the low-carbohydrate diet and −0.19 mmol/L [−7.4 mg/dL] with the low-fat diet; P = 0.2). Minor adverse effects were more frequent in the low-carbohydrate diet group.
Conclusions: Compared with a low-fat diet, a low-carbohydrate diet program had better participant retention and greater weight loss. During active weight loss, serum triglyceride levels decreased more and high-density lipoprotein cholesterol level increased more with the low-carbohydrate diet than with the low-fat diet.
- “Comparison of high-fat and high-protein diets with a high-carbohydrate diet in insulin-resistant obese women”, by K. A. McAuley, et al. Diabetologia, Volume 48, Number 1, 8-16, DOI: 10.1007.
Results: Body weight, waist circumference, triglycerides and insulin levels decreased with all three diets but, apart from insulin, the reductions were significantly greater in the HF and HP groups than in the HC group. These observations suggest that the popular diets reduced insulin resistance to a greater extent than the standard dietary advice did. When compared with the HC diet, the HF and HP diets were shown to produce significantly (p<0.01) greater reductions in several parameters, including weight loss, waist circumference, and triglycerides. Cholesterol decreased in individuals on the HC and HP diets but tended to fluctuate in those on the HF diet to the extent that overall levels were significantly lower in the HP group than in the HF group. Of those on the HF diet, 25% showed a >10% increase in LDL cholesterol, whereas this occurred in only 13% of subjects on the HC diet and 3% of those on the HP diet.
Conclusions/interpretation: In routine practice a reduced-carbohydrate, higher protein diet may be the most appropriate overall approach to reducing the risk of cardiovascular disease and type 2 diabetes. To achieve similar benefits on a HC diet, it may be necessary to increase fibre-rich wholegrains, legumes, vegetables and fruits, and to reduce saturated fatty acids to a greater extent than appears to be achieved by implementing current guidelines. The HF approach appears successful for weight loss in the short term, but lipid levels should be monitored. The potential deleterious effects of the diet in the long term remain a concern.
- “Effect of a Low-Carbohydrate Diet on Appetite, Blood Glucose Levels, and Insulin Resistance in Obese Patients with Type 2 Diabetes”, by Guenther Boden, MD; et al. Annals of Internal Medicine, March 15, 2005. vol. 142 no. 6 403-411.
Results: On the low-carbohydrate diet, mean energy intake decreased from 3111 kcal/d to 2164 kcal/d. The mean energy deficit of 1027 kcal/d (median, 737 kcal/d) completely accounted for the weight loss of 1.65 kg in 14 days (median, 1.34 kg in 14 days). Mean 24-hour plasma profiles of glucose levels normalized, mean hemoglobin A1c decreased from 7.3% to 6.8%, and insulin sensitivity improved by approximately 75%. Mean plasma triglyceride and cholesterol levels decreased (change, −35% and −10%, respectively).
Limitations: The study was limited by the short duration, small number of participants, and lack of a strict control group.
Conclusion: In a small group of obese patients with type 2 diabetes, a low-carbohydrate diet followed for 2 weeks resulted in spontaneous reduction in energy intake to a level appropriate to their height; weight loss that was completely accounted for by reduced caloric intake; much improved 24-hour blood glucose profiles, insulin sensitivity, and hemoglobin A1c; and decreased plasma triglyceride and cholesterol levels. The long-term effects of this diet, however, remain uncertain.
- “Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet”, by Iris Shai, R.D., Ph.D., et al. N Engl J Med 2008; 359:229-241, July 17, 2008.
Results: The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years. The Mediterranean-diet group consumed the largest amounts of dietary fiber and had the highest ratio of monounsaturated to saturated fat (P<0.05 for all comparisons among treatment groups). The low-carbohydrate group consumed the smallest amount of carbohydrates and the largest amounts of fat, protein, and cholesterol and had the highest percentage of participants with detectable urinary ketones (P<0.05 for all comparisons among treatment groups). The mean weight loss was 2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet group, and 4.7 kg for the low-carbohydrate group (P<0.001 for the interaction between diet group and time); among the 272 participants who completed the intervention, the mean weight losses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The relative reduction in the ratio of total cholesterol to high-density lipoprotein cholesterol was 20% in the low-carbohydrate group and 12% in the low-fat group (P=0.01). Among the 36 subjects with diabetes, changes in fasting plasma glucose and insulin levels were more favorable among those assigned to the Mediterranean diet than among those assigned to the low-fat diet (P<0.001 for the interaction among diabetes and Mediterranean diet and time with respect to fasting glucose levels).
Conclusions: Mediterranean and low-carbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions.