Archive for December, 2005
Until midnight tomorrow the registration fees for the upcoming 2006 NMS Scientific Sessions: Nutritional & Metabolic Aspects of Carbohydrate Restriction remain discounted for early-bird registration.
It’s not too late to register to attend and learn about the compelling research that shows carbohydrate restriction is supported by scientific evidence as an option for those with many metabolic disorders including diabetes, metabolic syndrome, PCOs and obesity.
While traditional conferences of this type tend to be exclusively attended by those within the research and medical communities, this one is also open to the public and industry! I strongly encourage those of you who are interested in controlled-carb nutrition to consider attending. There will be many presentations that are going to be easily understood by those who are not doctors or academic researchers and plenty of folks on-hand to answer any questions you may have!
The registration includes all conference materials, an attendee welcome bag, your breakfast and lunch each day, snacks and a one-year membership in the Nutrition & Metabolism Society. The conference is in Brooklyn, New York – Janaury 20-22, 2006 and the hotel is even offering a discounted room rate!
If you have the time and the budget, this is one conference you want to attend! Register today so you don’t miss the discounted early-bird registration!
Since starting this blog back in May 2005, I’ve tackled a number of subjects related to health, nutrition and lifestyle. With the vast majority of subjects, I’ve sought to bring my readers the scientific evidence in an easy to understand format. Occassionally I’ve offered my own opinions and thoughts on some things with the hope that such opinions make sense and are also based on my evaluation of the data available.
I thought I’d use today’s column as a review of the year’s top ten important headlines. Let’s count down to number one…
10 – The Role of Inflammation in Disease
Throughout 2005 research data continued to reveal how insidious inflammation is to our health. I’m not talking about the type of inflammation from a sports injury or when you bump your arm, but the low-level chronic type of inflammation that you don’t feel and don’t know is there until it’s too late. Since May I’ve included information about the damaging effects of inflammation in ten articles, with the two most important being: Death by Inflammation and Inflammation and Metabolic Syndrome.
9 – Debate about Metabolic Syndrome – Does it Exist?
Two of the leading health organizations in the United States are battling over whether Metabolic Syndrome is real or not. The American Diabetes Association issued a position paper stating that Metabolic Syndrome should not be a diagnosis unto itself and clinicians should treat the features considered part of the disorder rather than treat a cluster of symptoms. The American Heart Association took little time to issue their own position paper stating that Metabolic Sydrome is indeed a disorder to be diagnoised and treated – to ignore the clustering of features is a mistake for clinicians.
A good article about the two sides of the debate is found in the October 10, 2005 Business Week.
8 – 2005 Dietary Guidelines for Americans and Food Guideance Pyramids
The government issued revised Dietary Guidelines for Americans and a series of Food Guideance Pyramids this year. While those who believe such guidelines are useful were quick to praise and promote them, I have written extensively about the flaws within them – namely the risk of failing to consume adequate intake of essential micronutrients, amino acids and fatty acids. In the article, Examining Low-Carb and Low-Fat Diets: Part 2, I compare, side-by-side, a low-fat menu and a low-carb menu to highlight the nutrient deficiency in the low-fat menu.
7 – Protein and Satiety
It wouldn’t be a stretch to say that the importance of protein in the diet came to the forefront of our understanding of satiety this year. A number of studies published continued to show the power protein has on feeling full and that when protein is increased in the diet, it is easier to stick with a weight loss program. In the article, Study Finds Controlling Carbohydrate Better, you’ll find more information about the role of protein in the diet and satiety.
6 – DASH Diet better with fewer carbohydrates
Quite frankly, the DASH Diet is no longer the DASH Diet if you increase protein and reduce carbohydrate, but that didn’t stop the headlines from proclaiming this “tweak” showed the diet was more effective with less carbohydrate! You can read more about this finding in DASH Diet Better with Less Carbohydrate.
5 – Fructose and Obesity
A large number of studies were published in 2005 that implicated fructose as a culprit in our obesity epidemic. In the article, Fructose and Obesity, I detail the results of a study that showed mice fed a steady diet of fructose had 90% more body fat than mice fed water, even though the mice consuming water ate more calories!
4 – Childhood Obesity and Adult Disease
Our children are not only growing more overweight each year, they’re now starting to suffer the same diseases as their overweight and obese adult counterparts. Researchers are now cautioning that if we do not reverse this trend, our children will have a shorter life expectacy than we do. In The Future is Now, I detailed the findings of a survey investigating the incidence of overweight in children. The findings were scary!
3 – The Importance of Vitamin D in health
Many take for granted they’ll consume foods that provide for their essential micronutrients in their diets each day. The research however continues to show that a number of vitamins, minerals and other essentials are critically low in our diets and some of the things we do in our daily life contributes to our inability to meet our nutrient requirements. Vitamin D is one of those critical nutrients that is tricky to consume in food and we can make with exposure to sunlight. My most recent article, Vitamin D is Critical for Health, discusses the finding that vitmain D can reduce risk of cancer and provides a list of foods that have vitamin D.
2 – Longer Term Data – 22-month study – shows Low-Carb Effective for Diabetics
We hear a lot about the need for long-term data before we start considering different dietary approaches than those already recommended. This is especially true when it comes to low carbohydrate diets being recommended to those with metabolic disorders like Diabetes. This month, the first such “long-term” data was found in a poster published at the Nutrition & Metabolism Society website. You can find more about the research findings in Diabetics, Take Notice! Researchers conclude Low-Carb Diet is an Effective Treatment with 22-Month Data.
1 – Features of Metabolic Syndrome the very ones Low Carb Diets reverse
In Connecting the Dots, I detail the review published in the journal Nutrition & Metabolism that found the features of Metabolic Syndrome are the very same list of things that reverse with a low-carbohydrate diet – high triglycerides, low HDL (good cholesterol), high blood sugar, high blood pressure, insulin resistance and obesity. Without a doubt, to me, this is the number one item for the year. With an estimated 25% of all adults in the US showing features of Metabolic Syndrome, these findings should be setting off alarm bells that there is something wrong with our diet and that there is something that reverses the problem – reducing carbohydrate!
While the above represents those items I believe were the top ten for 2005, many more items could also be included – diabetics are not controlling their blood sugars as well as they should, tight control does make a difference for diabetics, the food industry seeks and gets protection for lawsuits in a number of states, etc.
What the above highlights is that the research continues to show that our current recommendations for population-wide consumption of a low-fat diet are flawed. While such a dietary approach may be beneficial for some, it certainly is not for everyone. I believe in 2006 we are going to witness a strong campaign to discredit and dismiss any dietary approach outside the current low-fat paradigm more strongly than ever before.
Keep your eyes on the evidence, not the headlines. Keep your mind active and seek out the information to build your understanding of how your metabolism works and how what you eat does have an effect on your health. Eat well, eat nutrient-dense and most of all, eat to live well!
Have a joyous and prosperous New Year! Here’s to your health!
Many of my readers may recall that I wrote back in June that 2005 is the year for insight into the critical importance of Vitamin D in our health. Today, MSNBC had an article, Study: Vitamin D lowers risk of major cancers, that drives home just how important this micronutrient is for our long-term health.
The MSNBC article does a good job of presenting the results from the research.
I’m just going to add here that the article did not include many of the foods that contain Vitamin D naturally, so I’ll list some here. I do not include margarine or milk since both have Vitamin D added, but it is noteworthy that fortified milk products are also a source of Vitamin D in the diet. I do not, however, recommend margarine.
1-tablespoon of butter contains 0.2mcg Vitamin D
- Heavy Cream
1-tablespoon of heavy cream contains 0.4mcg Vitamin D
- Natural Cheddar Cheese (regular)
1-ounce of regular, natural cheddar cheese contains 0.09mcg Vitamin D
- Natural Swiss Cheese (regular)
1-ounce of regular, natural swiss cheese contains 0.31mcg Vitamin D
1 large egg (specifically the yolk) contains 0.65mcg Vitamin D
- Canned Pink Salmon
3-ounces of canned pink salmon contains 10.2mcg Vitamin D
- Canned Tuna in Oil
3.25-ounces of canned tuna in oil contains 4.7mcg Vitamin D
(tuna packed in water has none)
2-tablespoons of liverwurst contains 0.38mcg Vitamin D
- Beef Liver, Braised
3-ounces of beef liver, braised contains 0.5mcg Vitamin D
- Gouda or Edam Cheese (regular)
1-ounce regular, natural gouda or edam cheese contains 0.2mcg Vitamin D
- Mixed Species Shrimp (moist heat cooked)
4-ounces of mixed species shrimp contains 1.62mcg Vitamin D
- Chinook Salmon, Baked or Broiled
4-ounces of chinook salmon contains 4.1mcg Vitamin D
- Pacific Cod, Baked or Broiled
4-ounces of pacific cod contains 0.64mcg Vitamin D
- Cod Liver Oil
1-teaspoon of cod liver oil contains 4mcg Vitamin D
This is not an exhaustive list, but interestingly, many of the foods above are the very ones we’re told to avoid in our diets in the US. Even more interesting, at least to me, is the fact that many of these very foods are the same foods encouraged when one is eating a low-carb diet!
While it can be tricky to get your Vitamin D from foods, it most definitely can be done. Supplements are also another way to boost your vitamin D intake – but remember, when vitamins occur in food they also occur with other vitamins, minerals and elements and these may be important to our ability to utilize the Vitamin D. So, from my perspective, it is better to try to get as much of your Vitamin D from food as possible, especially during the winter months when our exposure to sunlight is decreased.
Sunlight, by the way, is of critical importance for humans to make Vitamin D – without it, or when we slather ourselves with sunscreen all the time, we’re limiting our body’s ability to make the Vitamin D it needs. This isn’t to encourage reckless abandon in the sun – but to remind you that short-term exposure to sunlight is actually beneficial to your health.
That means that in the warmer months, exposing yourself to sunlight, sans sunscreen for 20-30-minutes each day is beneficial as is allows your body to manufacture Vitamin D from the exposure to the UV rays.
At least 89 articles appeared in the press since yesterday, claiming that research shows a diet that is high in fat can disrupt sugar levels and trigger diabetes. In the LA Times’ article is titled, “Enzyme Study Links Fatty Diets to Diabetes.“
The opening sentences are pretty convincing: Diets high in fat can disrupt blood sugar levels and trigger diabetes, researchers said Wednesday in a study that helps explain the link between obesity and a disease typically linked to sugar. Fatty foods can suppress an enzyme crucial to the production of insulin, which regulates sugar in the blood, scientists at UC San Diego said.
How many people participated in the study? None
You guessed it, this wasn’t a human study, it was an animal study. In this one, the participants were mice.
The normal diet of a mouse is about 5% fat, 15% protein and 80% carbohydrate – a very different macronutrient (fat, protein, carbohydrate) mix than we humans eat.
Now this isn’t to say that animal models are useless or unable to provide useful data – they are and they have for years. The real problem here isn’t the mice per se, it’s the media jumping up and down to say the data shows a high fat diet is detrimental for humans. Just look at the headline again.
Even the researchers themselves did not go that far!
The article states that:
“In a study of normal mice that were fed a fatty diet, researchers found that the enzyme was repressed, leaving pancreatic cells unable to sense sugar levels and leading to diabetes.
“Our findings suggest that the current human epidemic in Type 2 diabetes may be a result of GnT-4a enzyme deficiency,” said Marth, adding that people who inherit a faulty gene may also be vulnerable to diabetes.
It may also play a role in the early onset of Type 2 diabetes in children and teenagers, according to the study, which was also sponsored by the National Institutes of Health.”
I’ve bolded the important words above. “May” is not “definitive,” nor is “suggest” saying that the findings are “definitive.”
Hey, if nothing else, we know if we feed mice a diet that is high in fat, they’ll have problems. But, does the same hold true for humans?
Quite frankly, it depends on the context – the mix – of the diet one is eating.
If you’re eating a large amount of carbohydrates along with a large amount of fat, I’d be the first to tell you you’re heading for metabolic nightmares – this “opinion” is even supported by data. Just as the research data shows that if you reduce the carbohydrate and consume higher amounts of fat, well – metabolic disorders in humans tend to reverse – is also an “opinion” supported by data.
And here is where I feel researchers are “missing the boat” when it comes to nutrition studies – they’re still focused on macronutrient ratios and too focused on fat in the diet as a percentage of calories.
As I’ve pointed out before, if you’re eating 3,000 calories a day and trying to stay within 30% of those calories from fat, you’ll be eating about 100g of fat each day. Now let’s pretend you’re overweight and need to lose 50-pounds, so you reduce your calories to 2,400 calories a day.
Up until that calorie reduction you’ve eaten 100g of fat each day, within the “healthy” diet recommendations. If you decide to reduce your carbohydrate instead of your fat and continue to eat 100g of fat each day, the “experts” will now insist you’re eating unhealthy, even if reducing your carbohydrate means you’re increasing your intake of fresh vegetables while eliminating refined sugars and grains!
Their reasoning is that you’ve somehow “increased” your fat intake because you’re now eating 37.5% of your calories from fat instead of less than 30%.
It doesn’t matter that the glucose burden in your body has been reduced, thus reducing your insulin, by eliminating 150g of carbohydrate each day as your source of calorie reduction. Nope, you’re now eating too much fat….even though you’ve now reduced your calories and reduced your body’s need to shuttle sugar around and store it when it’s in excess amounts.
If the arguement is that calories in calories out are at the heart of weight loss, why then this obsession with dietary fat? Why not offer those who are overweight or obese – or even pre-diabetic or diabetic – an option of what macronutrient they find easier to reduce to reduce calories each day?
For those who are pre-diabetic or diabetic (type II specifically) the research shows that reducing carbohydrate is effective – not only for weight loss, but for improving insulin sensitivity, reducing fasting blood glucose levels, reducing LDL (bad) cholesterol, increasing HDL (good) cholesterol, reducing triglyerides and providing a greater feeling of satiety when followed correctly.
Data – from studies specifically on humans – show that higher percentages of dietary fat & protein with a lower percentage of carbohydrate calories offers many diabetics and pre-diabetics the ability to lose weight and reduce the features of their metabolic disorders. Yet we remain stuck in this thinking that one must reduce dietary fat to lose weight or to improve their health!
As I wrote about just a few days ago in Diabetics, Take Notice! Researchers conclude Low-Carb Diet is an Effective Treatment with 22-Month Data, we’re now seeing longer-term human data and it is showing promise that low-carb diets are an effective dietary therapy for diabetes.
Which begs the question – if you’re diabetic, which would you rather trust – human data or animal models in trying to determine the best course of treatment, with diet, while working with your doctor to monitor your progress?
”What right has the federal government to propose that the American people conduct a vast nutritional experiment, with themselves as subjects, on the strength of so very little evidence that it will do them any good?”
That was the question posed to Congress by Dr. Phil Handler, back in 1980 when he was the president of the National Academy of Sciences.
Just what “experiment” was he talking about?
The low-fat diet.
At the time, the United States had a fairly constant 13-14% of the population classified obese. Today, some 25-years later, we are living with the reality that two out of every three Americans are overweight and one of the two is obese. We’ve experienced a rise in obesity from a steady, predictable 13-14% to what now stands at one-third, 33%, of our population obese.
That alarming statistic isn’t declining either. In fact, our children are now experiencing obesity rates that rival the adults along with the detrimental health effects too – heart disease, type II diabetes, metabolic syndrome, high blood pressure, high cholesterol, etc.
Yet, the consensus opinion holds that the low-fat dietary recommendation is the ideal and we must remain steadfast with our recommendations. To question the low-fat diet is outright heresy. The belief that the low-fat diet is optimal is so strong that anyone who even voices concern runs the risk of public ridicule or worse, has their personal integrity and intellectual honesty questioned.
Take as an example, today’s article in The Age, Peers turn up heat on CSIRO diet. The article reports an editorial published in Nature that questions the integrity and intellectual honesty of two researchers – Dr. Manny Noakes and Dr. Peter Clifton – from CSIRO Human Nutrition (Commonwealth Scientific and Industrial Research Organisation, Australia).
What exactly have they done to earn the scorn of their colleagues?
They wrote the book CSIRO Total Wellbeing Diet – a high protein dietary approach based on their research findings. The book arose out of eight years of CSIRO research into lowering the risk of heart disease, during which it encountered the absence of scientific facts on the truth behind weight loss.
This wasn’t a book borne out of a six month study, or even a one or two or three year study – it was eight years of scientific research! Eight years of data that supports the authors’ recommendation that a higher protein diet is effective and safe.
Yet, the critics contend that “The hype goes beyond what the research proves,” said Jim Mann, from the University of Otago.
Where exactly is the proof that a low-fat diet is healthy?
I’ve said it before and I’ll say it again – to date there is NOT ONE long-term, randomly controlled study ever done to investigate the effects of a low-fat diet on human health over a long period of time. Even after repeated attempts to prove a low-fat diet is supported by scientific evidence, the government abandon trying to document such since there is not enough evidence to even cobble together a half decent paper to make that claim!
In fact, there exists MORE data telling us about the effects of various carbohydrate restricted diets – low-carb, controlled-carb, low glycemic index, high protein, etc. – than a low-fat diet at this point in time. Even the beloved DASH Diet, promoted by the NIDDK (National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health) was found more effective when carbohydrate was reduced and protein was increased!
The low-fat doctrine was questioned 25-years ago by one of the nation’s leading health experts at the time. He warned reducing fat in the diet was a grand population-wide experiment without solid scientific evidence to embark on with – he was ignored. Today we’re living the results of that experiment – as a nation we’re fatter than ever before and our health is worse.
If this does not anger you, I don’t know what will. You’ve been had – the emperor has no clothes!
You should be outraged!
The dietary recommendations we’ve listened to for the last 25-years, I contend, are directly contributing to our growing obesity and declines in health. It’s time to stand up and say ENOUGH – show me the long-term data that proves a low-fat diet is healthier than a diet that has fewer carbohydrates, show me the data that shows a controlled-carb diet is unhealthy!
They can’t. They won’t. But they will continue to dazzle you with dogma and claim the evidence supports their recommendations. They’ll continue to repeat the low-fat mantra to try to convince you without any evidence! Don’t be fooled by it.
Take the time in 2006 to educate yourself about how your metabolism works, what foods are nutrient-dense and how controlled-carb diets work. Don’t just take my word for it – it is your future – use 2006 to take back your life and your health!
Then watch throughout 2006 as the diet debates heat up, as more and more researchers are targeted as heretics with their integrity and honesty questioned. It is going to happen and it will be nasty as the evidence continues to mount that a low-fat diet is not optimal for population-wide recommendations. Those who are bringing forth such evidence are exposing the naked emperor for his lack of clothes and risking embarassment to those who insist he is clothed.
This isn’t the first time that science has undergone such radical shifts – in fact, it’s part of the scientific process of inquiry and learning. You just don’t have to wait for it to happen – the evidence is there that controlled-carb dietary approaches work and offer an alternative. If you’re not convinced, wait and see!
Diabetics, Take Notice! Researchers conclude Low-Carb Diet is an Effective Treatment with 22-Month Data
Today an abstract poster was published on the Nutrition & Metabolism Society website that will be featured during the upcoming 2006 NMS Scientific Sessions: Nutritional & Metabolic Aspects of Carbohydrate Restriction – Lasting improvement of hyperglycemia and bodyweight after 22 months: low-carbohydrate diet in Type 2 diabetes. [Last poster abstract, bottom of the page]
Researchers from Sweden have been following the progress of two groups of Type II Diabetics assigned two different dietary approaches for 22-months. The first group was assigned a low-fat diet that consisted of 55-60% carbohydrate, 15% protein and 20-25% fat – this group served as the “control group.” The second group was assigned a low-carbohydrate diet that consisted of 20% carbohydrate, 30% protein and 50% fat – this group served as the “study group.”
The results after the first six months and one year were promising for the low-carb diet group – as the researchers stated in their conclusions at that point in time: A low-carbohydrate diet is an effective tool in the treatment of obese patients with type 2 diabetes.
This was based upon the finding that, [p]ositive effects on the glucose levels were seen very soon. After 6 months a marked reduction in bodyweight of patients in the low-carbohydrate diet group was observed, and this remained one year later. After 6 months the mean changes in the low-carbohydrate group and the control group respectively were (+/-SD): fasting blood glucose (f-BG): -3.4+/-2.9 and -0.6+/-2.9 mmol/l; HBA1c: -1.4+/-1.1 % and -0.6+/-1.4 %; Body Weight: -11.4+/-4 kg and -1.8+/-3.8 kg; BMI: -4.1+/-1.3 kg/m_ and -0.7+/-1.3 kg/m_.
But – the data was only for one year and thus not “long-term” and therefore summarily dismissed by many as irrelevant. It did not matter that those diabetic patients following the low-carb diet were doing BETTER than those assigned the low-fat diet – what mattered was that they hadn’t followed the low-carb diet for more than a year.
Many within the diabetic healthcare community basically continued to advise their patients that low-carb diets were unsafe at worst, unproven at best. It didn’t matter that after a year, across the board, on every measure, those following the low-carb diet did significantly better:
- Lower fasting blood glucose
- Lower HBA1c levels
- Lost more body weight
- Reduced BMI more
This did not discourage the researchers! And, I for one am glad they continued to follow these patients. Now, after 22-months, we have a better picture of just how well those following a low-carb diet are doing. They’re not just doing well, they’re still doing better than those following the low-fat diet!
As the researchers point out in their results section: The mean weight has increased from month 6 to months 22 by 2.7 ± 4.2 kg. Seven of the 16 patients retained the same bodyweight from 6 to 22 months or reduced it further. Mean HbA1c which, after 6 months, was 6.6 ± 1.0 %, was 6.9± 1.4 % after 12 months and was still 6.9 ± 1.1 % at 22 months.
Because of the reduction in bodyweight and insulin resistance, a reduction in cardiovascular risk would be expected at some point. We examined medical charts for episodes of cardiovascular disease from 3 months after the initiation of the diet therapy – when an effect might be detected — and forward. Three episodes of cardiovascular disease occurred among the 5 patients that did not change their diet. The 16 patients in the LCG and the 10 from the CG that changed diet – totalling 26 patients — have been free of cardiovascular disease during the follow-up period (p = 0.002. Fischer Exact).
Their conclusion again: A low-carbohydrate diet is an effective tool in the treatment of obese patients with type 2 diabetes.
I don’t know about you, but if I were diabetic, I’d be asking my doctor why I’m being told to eat a low-fat diet and demanding to see the long-term data that shows it more effective than a low-carb diet. I’d be demanding to know why I’m being told to adjust my medications instead of my consumption of carbohydrate!
Then I’d be demanding the American Diabetic Association (ADA) start to take this dietary approach seriously and begin to craft an evidence-based guideline for my doctor to use in my treatment so I could reduce or eliminate many of the medications and/or insulin injections each day! I’d be telling them I’m tired of just managing my disease with pharmaceuticals – I want to be able to be free of the costly prescriptions and injections, and if a low-carb diet offers that as a possibility, it must be one of the options I am told about and offered as a management tool for my disease!
Folks, many believe the low-carb diet has been relegated to the dust-bin of fad diets that have come and gone. Nothing could be farther from the truth!
While the low-carb dietary approach may have lost its luster for the media it remains a strong candidate as a dietary approach for the management of diabetes, metabolic syndrome, high cholesterol and other metabolic disorders. It may have fallen out of favor with the popular press, but it is still going strong in research circles around the world.
It’s not often I totally rail someone in my blog. Today is, however, an exception.
A dietitian and nutrition consultant in Chicago was a featured writer today at the WTOP radio website with the article, “Taking a bite out of the glycemic index trend.” It is, without a doubt, a shining example of how the media misleads when it comes to advice about diet and nutrition because the writer does not do their homework.
In this instance, Ms. Helm, the writer, tackles the increasing popularity of low glycemic index diets and, through carefully crafted buzz words, seeks to convince the reader the approach is worthless and and lacks the ‘endorsement’ of leading health organizations as a method to control diet for weight loss. In lock-step with the current party-line she believes that this lack of endorsement is some proof that low glycemic diets lack scientific merit and goes on to parrot recent opinions of research findings that claim the results show low GI diets offer no benefit.
Dr. Susan Raatz, a researcher from the University of Minnesota Medical School, who recently published one study, Reduced Glycemic Index and Glycemic Load Diets Do Not Increase the Effects of Energy Restriction on Weight Loss and Insulin Sensitivity in Obese Men and Women, is quoted as saying “Calories are what really count, low GI is not adding any magic bullet to improve weight loss.”
I wrote an article about her study October 26, 2005 right here in this blog – Weight Loss: Glycemic Index (GI) and Glycemic Load (GL) – and paid to have access to the full text of her published research data.
Guess what the data showed?
You guessed it – low GI diets did indeed provide a benefit. Too bad Dr. Raatz doesn’t have the guts to actually state the facts from her own data!
The benefit wasn’t actual pounds lost, even those those who followed the low-GI diet did indeed lose more weight – 1.4-pounds more at the end of 12-weeks. This was just what is known as statistically insignificant. I don’t know about you, but if I were trying to lose weight and I lost 1.4 pounds more at the end of 12-weeks, it would matter to me.
But, as I said, the benefit statistically was not actual pounds lost. It was, instead something much more important – those following the low-GI diet LOST LESS LEAN BODY MASS and MORE BODY FAT. And not just a minor difference.
In fact, here is the actual data from the study:
At 12-weeks, the real pounds lost by each group was calculated as:
- High-GI lost 9.3kg average, or 20.5-pounds
- High-Fat lost 8.4kg on average, or 18.5-pounds
- Low-GI lost 9.95kg on average, or 21.9-pounds
At 12-weeks, the lean body mass (LBM) lost by each group was calculated as:
- High-GI lost 4.8kg on average, or 10.6-pounds of LBM
- High-Fat lost 2.6kg on average, or 5.7-pounds of LBM
- Low-GI lost 3.04kg on average, or 6.7-pounds of LBM
At 12-weeks, the body fat lost by each group was calculated as:
- High-GI lost a total of 20.5-pounds, with 10.6-pounds of LBM, for a fat loss of 9.9-pounds
- High-Fat lost a total of 18.7-pounds, with 5.7-pounds LBM, for a fat loss of 12.8-pounds
- Low-GI lost a total of 21.9-pounds, with 6.7-pounds of LBM, for a fat loss of 15.2-pounds
Hello? Anyone home? Which do you think is a healthier weight loss?
Remember, Dr. Raatz said that “Low GI is not adding any magic bullet to improve weight loss.”
Losing significantly more body fat and significantly less lean body mass isn’t better?
Ms. Helm doesn’t stop there though. She moves on to highlight that the committee to revise the Dietary Guidelines for Americans “dismissed” the concepts of the glycemic index, and continued with “reinforcing the notion that “calories in vs. calories out” matters most.
She then takes it a step further to state that the American Diabetes Association has “not endorsed the use of the GI for weight loss.” To bolster this, she quotes Marion Franz, an ADA advisor whom Helm writes is a “diabetes expert,” who says that “The original intent of the glycemic index is being misinterpreted by the diet books.” Franz said the concept of the glycemic index may help people with diabetes “fine-tune” their food choices, but there’s little evidence it will enhance weight loss. Most of the weight-related claims – from curbing cravings to increasing energy – are unsubstantiated, she said.
Here, we have an “expert” quote that puts the nail in the coffin of the glycemic index. Not only are we to believe that glycemic index offers no benefit to weight loss, but we’re also now to believe that low glycemic index foods will not offer satiety value, curb cravings or increase energy. Add to that the very strong words that such “claims” are said to be “unsubstantiated.”
So the overall picture painted is that glycemic index offers no benefit for weight loss, is useless, does not increase satiety, doesn’t help with calorie control, will not curb cravings and provides no increase in energy.
You don’t have to be a rocket scientist to search PubMed.com, the National Institutes of Health (NIH) database of published research. A cursory search of “glycemic index” and “satiety” returned 37 results.
Within the abstracts we find some interesting statements or conclusions:
Dr. Ludwig: Physiological studies demonstrate that consumption of high GI/GL meals induce a sequence of hormonal changes that limit availability of metabolic fuels in the post-prandial period and cause overeating. Short-term feeding studies consistently show less satiety or greater voluntary energy intake after consumption of high compared to low GI meals.
Dr. Jimenez-Cruz: Eating a lunch with a low GI index resulted in higher satiety perception. These results suggest the need to promote culturally based combined foods with high fiber and low GI. This approach might contribute to the prevention of obesity by increasing the perception of satiety while also improving metabolic control of diabetics.
Dr. Kabarnova: Different metabolic consequences of the intake of individual fatty acids (polyunsaturated and n-3 fatty acids vs. saturated fatty acids), individual carbohydrates (low vs. high glycaemic index carbohydrates) and fibre should be considered during the weight management.
Dr. Warren: The type of breakfast eaten had a statistically significant effect on mean energy intake at lunchtime: lunch intake was lower after low-GI and low-GI with added sucrose breakfasts compared with lunch intake after high-GI and habitual breakfasts (which were high-GI).
Dr. Roberts: We examine whether the consumption of low-glycemic index (GI) carbohydrates may facilitate a reduction in energy intake in obese people attempting to lose weight. Although data from long-term studies are lacking, short-term investigations indicate that consumption of low-GI carbohydrates may delay the return of hunger and reduce subsequent energy intake relative to consumption of higher-GI carbohydrates.
It seems Ms. Helms, Ms. Franz and Dr. Raatz don’t exactly hold the same opinion as many of their esteemed colleagues, does it?
So then, what’s the real deal?
For one, the research into the usefulness of glycemic index remains open to interpretation.
The approach to managing diet with an eye on glycemic index shows promise yet lacks the clarity we need to effectively establish it as a guideline for consumers. This is due to the fact, as Ms. Helms article states, “[t]he GI ranking of a food also can vary dramatically depending on how you prepare it and how much you eat – which makes it difficult to nail down the actual number.” One of the accurate statements in her article.
This lack of clarity is exactly why continued research is critical. We now understand that the glycemic index itself has limitations as a tool. This understanding led to the further research that provided another perspective to consider – the glycemic load. Researchers are finding that the overall dietary glycemic load does indeed play a role in our metabolic response to food and thus our weight and health.
Dr. Jennie Brand-Miller is one of the leading authorities on glycemic index and glycemic load who does research out of the School of Molecular and Microbial Biosciences, University of Sydney, Sydney, Australia. I’ve met her and can say she’s one sharp lady. In a recent letter in Diabetes Care, she and her co-authors provide some great insights:
In their prospective analysis of a cohort of 36,000 adults followed for 4 years, Hodge et. al found that higher-carbohydrate diets were associated with a lower risk of development of type 2 diabetes. However, the type of carbohydrate was equally important: low-GI carbohydrates reduced the risk, while high-GI carbohydrates increased the risk. Thus, low GI and low GL are not equivalent and produce different clinical outcomes.
Because this issue may be confusing to some readers, it is important to clarify the difference between GI and GL. Both the quality and quantity of carbohydrate determines an individual’s glycemic response to a food or meal (2).
By definition, the GI compares equal quantities of available carbohydrate in foods and provides a measure of carbohydrate quality. Available carbohydrate can be calculated by summing the quantity of available sugars, starch, oligosaccharides, and maltodextrins. As defined (3), the GL is the product of a food’s GI and its total available carbohydrate content: glycemic load = [GI x carbohydrate (g)]/100.
Therefore, the GL provides a summary measure of the relative glycemic impact of a “typical” serving of the food. Foods with a GL 10 have been classified as low GL, and those with a value 20 as high GL (4). In healthy individuals, stepwise increases in GL have been shown to predict stepwise elevations in postprandial blood glucose and/or insulin levels (5).
It can be seen from the equation that either a low-GI/high-carbohydrate food or a high-GI/low-carbohydrate food can have the same GL. However, while the effects on postprandial glycemia may be similar, there is evidence that the two approaches will have very different metabolic effects, including differences in ß-cell function (6), triglyceride concentrations (7), free fatty acid levels (7), and effects on satiety (8).
Where I disagree with Dr. Brand-Miller is her caution that, “Our concern is that the use of the GL or “glycemic response” in isolation may lead to the habitual consumption of lower-carbohydrate diets. “
Personally, I don’t see a lower-carbohydrate diet as being a problem – especially when I consider the continued publication of research findings that are still showing that a lower (controlled) carbohydrate diet is safe and effective – not only for weight loss, but weight maintenance and management of a host of health issues.
But, I digress…
While this article is lengthy, it highlights how important it is to seek out information for yourself and educate yourself about what the actual data from studies shows. Opinions are not evidence and the article from Ms. Helms is littered with opinions. Not only that, it also lacks support from hard data and a full view of what a broad range of researchers are saying!
Is the glycemic index confusing? Yes
Does glycemic load values make it moreso? Probably
Is such an approach useless, providing no benefit? Absolutely NOT!
What we see here, again, is an article that looks to dismiss the research and get you to just ignore the evidence and get in lock-step with the Dietary Guidelines for Americans. I previously wrote about the same type of call for dismissal by Dr. David Katz from the Yale School of Public Health.
Don’t fall for it!