Changing dietary trends and the obesity epidemic
Dinner tonight at Casa Eades
Last Sunday the New York Times published a color spread on the US Department of Agriculture (USDA) data on the changes in food consumption in this country between 1970 and 2006, which got me to musing.
To the uninformed, which, sadly, probably means most people working in the nutrition industry and even those employed in a nutritional capacity at the USDA, these changes (all save two) seem to be in a positive direction. The intake of dairy products has decreased; the intake of vegetables has increased; the intake of red meat has fallen; the intake of fish, chicken and skyrocketed; the intake of fruit is up; the intake of grains has increased markedly; and the intake of vegetable fats has almost doubled. The only two negatives are that sugar and sweeteners have increased and overall food consumption has gone up by about 11 percent, or an addition 1.8 pounds per person per week.
At the same time all these positive changes have been taking place, changes that all the (misinformed) people in the mainstream nutritional biz have been advocating, there has been an enormous increase in the rate of obesity. According to the Centers for Disease Control (quoted in the Times article) the rate of obesity has more than doubled since 1970, which is interesting because up until 1970 the rates of obesity hummed along at about the rate of 15 percent for decades.
What has happened since 1970 to cause this enormous societal change?
If asked, people give many answers: too much saturated fat, too much refined carbohydrate, too much food, etc.
I have my own opinions, which I will elaborate. I believe that the obesity epidemic has probably been driven by several dietary changes that have occurred since 1970. These changes are an increase in fructose and vegetable oil consumption and a decrease in saturated fat consumption. I believe that another contributing factor is the increased overall consumption of carbohydrates, which leads to an increased food consumption in general.
I want to emphasize that these are my opinions based on a pretty good knowledge of nutrition, metabolism, biochemistry, and physiology.
First, a sort of no-brainer. Since the USDA came out with the idiotic Food Pyramid we all loathe, there has been a major strategy in the food industry to move away from fats and toward carbohydrates. We have all seen this in various food consumption statistics. And we can tease it out from this Times piece if we look at which foods have increased and which have decreased in the diet. There has been a large increase in carbohydrate consumption as evidenced by the large increase in grains, vegetables, fruits and sweeteners.
Forgetting about all the metabolic events that carb intake precipitates that we all know cause obesity (i.e., increased blood sugar, increased insulin, etc.), let’s focus on simply one of the brain processes that carbs affect. The satiety center, located in the hypothalamus, is the part of the brain that tells us when we’re full. Unfortunately, it runs about 20-30 minutes behind our actual eating pattern, so we can stuff food in for a good while before our brains tell us we’ve had enough. Fortunately, it works a little more quickly (thanks to the help of cholecystokinin and some other gut hormones) when we eat primarily fat. If you eat a big steak, you feel full more quickly than if you eat a lot of carbs. Carbs tend to override the satiety center, allowing you to eat more. Let me describe a situation we’ve all experienced, and you’ll see what I mean.
You’re at a restaurant. You’re just at the end of a big meal and you’re stuffed. One of your dinner partners asks you to try a bite of his wonderful swordfish. It’s the best he’s ever tasted, he tells you. You say, I just can’t eat another bite. If I do, I’ll be sick. Then appears the waiter with the dessert tray, loaded with wonderful gooey treats. You look them over and say: I’ll take the carrot cake (or the chocolate mousse or whatever). How can you eat this calorically-laden dessert when you’ve just refused a bite of meat because you were so full? Because your brain’s satiety center is overridden by the carbs. And you haven’t even eaten the carbs yet. But experience has taught you that no matter how full you seem to be, there is always room for carbs. And fat, since most desserts are pretty high in fat as well. But it’s the carbs that do the satiety-center-blunting trick. It’s the reason dessert is always at the end of the meal. If you ate the dessert first, you would never be able to eat all the steak. And this carb overriding of the satiety center is why people don’t binge on steak, eggs and bacon. They binge on cake, chips, cookies and other high carb treats because they can stuff them without their satiety center telling them they’re full.
Since we’ve (as a nation) significantly increased our carb intake, it only makes sense that we’ve also increased the overall amount of food we eat. Carbs let us do that without even trying.
We have definitely increased our intake of fructose since 1970. I used the figures in the Times article to make my own calculations. Considering that table sugar is one half fructose and high-fructose corn syrup is 55 percent fructose (the most commonly used variety; some go as high as 90 percent fructose), I calculated that we ate about 50 grams of fructose per capita per day in 1970. By 2006 that figure had increased to 75 grams, a 50 percent increase. And we’ve got to bear in mind that these are average figures. I eat maybe 3 grams of fructose per day, and MD eats the same. That means that two other people out there are eating their 75 grams plus our extra 72 to make the averages come out as they do. I would suspect that most of the people reading this blog eat very little fructose, leaving a lot of other people to consume their share to keep the averages up.
But even 75 grams of fructose is a helluva lot. A little fructose – the amount you might find in a piece of fruit, for example – actually helps with glucose metabolism. It more or less primes the pump so that less insulin is required to reduce blood glucose. Large amounts of fructose are a different story, however. Fructose bypasses the enzyme phosphofructokinase, which is the rate-limiting enzyme in the glucose metabolism pathway. Consequently, large amounts of fructose are shunted past the sugar-regulating pathways and into the fat-formation pathway instead. The liver converts this fructose to fat, much of which, unfortunately, remains in the liver. ( Here is a nice paper on fructose metabolism. Ignore the idiotic conclusion, which is just another ad hoc attempt to make the data fit a preconceived notion acceptable to all academics.)
With continued consumption of large amounts of fructose, fat tends to accumulate in the liver leading to a condition called non-alcoholic fatty liver disorder (NAFLD). At this point, not only are we in an obesity and a diabetes epidemic, we are in an epidemic of NAFLD. Studies on ‘normal’ adults have shown that a little more than a third have significant fat accumulations in their livers. Even worse, 15-20 percent of children show the same thing.
NAFLD is the same disease people get who chronically over consume alcohol. Under the microscope NAFLD looks exactly the same; pathologically it acts the same. The only way to differentiate is by history of alcohol consumption: if there is fat in the liver and no history of chronic alcohol abuse, then NAFLD it is.
NAFLD has the same progression as the alcoholic variety. First, an accumulation of fat that becomes inflamed leading to a condition called non-alcoholic steatohepatitis (NASH), which means a non-alcoholic inflammation of fat in the liver. This condition can then progress to liver fibrosis, then to cirrhosis, then, ultimately, to liver cancer. Not all NAFLD follows this complete progression just as not all alcoholics get cirrhosis, but enough follow it to not make you want to get NAFLD if you can help it.
And one of the big ways not to get it is to avoid fructose.
By increasing fat in the liver, fructose also increases circulating insulin levels, which can lead to hyperinsulinemia and insulin resistance. How? Because a liver full of fat doesn’t work as well as a non-fatty liver. One of the jobs of the liver is to metabolize hormones and clear them from the circulation when their work is done. When you consume carbs or protein you stimulate the release of insulin to deal with them. Once insulin has done its job, the liver breaks it down to its amino acid components and puts them back in the circulating amino-acid pool. If the liver is filled with fat, it can’t do this as well. Insulin stays elevated (and in a diabolical twist even stimulates more fat synthesis in the liver) and tends to downregulate the insulin receptors, making them less responsive. The entire process can lead to insulin resistance, hyperinsulinemia and ultimately to obesity.
Below is a nice chart showing how the increase in obesity has paralleled the rapid increase in sugar consumption. Remember that table sugar is half fructose. Also remember that correlation is not causation. But in this case we do have the biochemistry of why worked out.
From Johnson RJ et al, AJCN 2007; 86:899-906
What about saturated fat? How does a decrease in saturated fat cause obesity. First, the decrease in saturated fat has tracked with the increase in vegetable oils, which are typically rich in omega-6 fats. Omega-6 fats have been shown in numerous studies to be proinflammatory. They have also been shown to worsen alcoholic fatty liver disease, and, one would assume, NAFLD as well. I haven’t seen any studies showing a worsening of NAFLD with increased consumption of vegetable oil – it hasn’t been studied as far as I know. (Maybe one of you readers can dig up a paper.) But it has been shown repeatedly with alcoholic liver disease, and since NAFLD is basically the same disorder, it makes sense that vegetable oil would worsen NAFLD as well. And if vegetable oil indeed does worsen NAFLD, then it promotes obesity by the mechanism described above.
Saturated fat is a healthful food. Read this article by Mary Enig that describes in detail the health benefits that come from eating saturated fat. I’ll address a couple of different issues.
Saturated fat is, well, saturated. That means that every carbon in the fatty acid chain has a full complement of hydrogens attached to it. There are no double bonds. In the picture below you can see a saturated fatty acid on top and a monounsaturated (one double carbon-carbon bond) fatty acid on the bottom.
Double bonds make fats unstable. These double bonds are the places that free radicals strike to convert unsaturated fats into peroxides, or oxidized fats. The more carbon-carbon double bonds a fatty acid has, the more susceptible it is to oxidation. Oxidized fats don’t function as well as non-oxidized fats. They make faulty cell membranes and less than optimal membranes for all the organelles within the cell. Oxidized fats can themselves become free radicals attacking adjacent fats and damaging them, or worse, starting an entire free-radical-fat-damaging cascade. All these forces work even more effectively at higher temperatures, so unsaturated fats shouldn’t be used for cooking. Unless, of course, your goal is to eat oxidized fats.
Saturated fats have no double bonds. They are immune to free radical attack. They are immune to heat damage. You can cook with them, you can hit them with a hammer, you can throw them on the floor and jump up and down on them. And they stay the same. Saturated fats are stable fats.
Most people don’t realize this, but the body has the ability to convert saturated fats to unsaturated fats. But the body doesn’t have the ability to convert unsaturated fats to saturated ones. The body can make saturated fats (palmitic acid, a 16-carbon-chain fatty acid) from excess carb consumption, but it can’t make a saturated fat out of an unsaturated one. If nature hadn’t wanted us to have saturated fat, why did she make us so that we make our own if we eat too many carbs. Could it be that during our evolutionary past the only time we might over consume carbs would have been when there was no meat available…and we needed the saturated fat? Sounds reasonable to me.
We have enzymes called desaturases that desaturate, i.e., add carbon-carbon double bonds, fats. We can take unsaturated fats and make them more unsaturated. And we can take saturated fats and make them unsaturated. But we can’t go the other way. In order to have saturated fats that provide the necessary structural stability that only saturated fats can provide is to get them in the diet, which we can do by eating saturated fats or by eating a whole lot of carbs. Since over consuming carbs comes with its own set of problems that we would rather avoid, that leaves eating saturated fats.
So how does avoiding saturated fats lead to obesity. In my opinion in a couple of ways. First, indirectly, by having them replaced by vegetable oil, particularly hydrogentated vegetable oil, i.e., trans fat. Due to their stability, saturated fats have cooking properties that no other natural fats have. Food chemists have created trans fats to have the same cooking properties – and in some situations even better cooking properties – as saturated fats. But the addition of trans fats to the diet creates a host of other problems. The medical literature is crawling with studies showing that trans fats drive the development of obesity.
The other reason is that saturated fats compose the lion’s share of normal membranous fats and of the brain. When membranes don’t work as well, especially mitochondrial membranes, our energy storage and regulation system doesn’t work as well. Anything that impairs membrane functioning impairs signaling function. If signaling function falls off, then various hormones, neurotransmitters, etc. lose function. As insulin loses function, more insulin is required, more insulin leads to more downregulation of receptors, all of which ultimately leads to obesity.
Even overeating carbs doesn’t help even though saturated fats are produced as a result. Carbs stimulate the production of palmitic acid, a 16-carbon chain fat. For proper membrane function and signaling we need shorter-chain saturated fats as well. These we can’t make – we get them from diet only. We can make shorter fats longer with elongase enzymes, but we can’t make longer fats shorter. We’ve got to get them via mouth.
Since this is speculation on my part – educated speculation, but speculation nevertheless – we may ultimately find that there are other reasons for the obesity epidemic instead of these or in addition to these. In fact, I can think of a few other minor causes, which I’ll save for a later post.) But I’ll bet that when all the work is done – which may not be for a hundred years given the academic climate of today – I’ll bet these ideas will be close to the mark.
Also off-topic, but something I’d love to get your and others’ opinion on. Whilst people are battling to eat the right foods and being told one thing by the establishment but learning other truths on this site and elsewhere, scientists are working hard to fool our bodies into thinking one food is another (e.g. artificial sweeteners.) In this short article I ask whether scientists will one day succeed in doing this to such an extent that the doctrine of self-discipline to which many of us subscribe will no longer apply. In particular I am interested in whether the mechanisms I suggest they might use seem plausible and how our lives might change.
The Professor Diet Part Two: Healthy Junk Food
Thanks!
Methuselah
Pay Now Live Later
Interesting and thought-provoking article. Thanks for sending.
Related to this somewhat, Jimmy Moore had a recent post about a doctor that wrote a book blaming fructose alone for the obesity epidemic. It was interesting and Gary Taubes countered somewhat…
Here my post to Jimmy’s article:
Very interesting! I think it is true that sugar is worse than starchy carbs. Why do I say this? My grown-up sons are pretty much sugar-free 99% of the time, however, they did not adopt my low-carb lifestyle. They will eat white buns and large flour tortillas, potatoes, rice and the like. They are both very slender and don’t exercise a huge amount as they are computer guys/techies. When I have made desserts, it has been with Splenda the whole time they were growing up. My eldest son does not indulge in desserts very often. He only likes apple desserts. LOL I can’t believe he is my son! As well, he does not care for chocolate. How is this possible?
Sure, they are young, however, there are many young people that eat the same way as they do, but also add large amounts of sugar to their diet – and the result is sometimes (not always – good genes, perhaps?) too much weight gain, and sometimes even diabetes develops at a young age.
The other thing is our sons don’t eat too frequently. They eat two meals a day, typically, and, therefore, less insulin is produced, right?
I think sugar and high fructose corn syrup are probably more dangerous than the starches, however, they are probably worst in combination with starches. The starches that are the least offensive, I think, are starchy veggies. These days the boys say I have a carb conscience. I don’t like having white flour or sugar, but I will have starchy veggies from time to time. When I indulge in the former, my carb conscience gives me trouble.
Certainly, when our metabolisms have a problem (mine, unfortunately from sugar soda abuse in my youth and also a low thyroid disease, Hashi’s) with carbohydrates, the cure is to go easy on those.
Just my opinions – and I’m sure because everybody is so very different, this hypothesis may not hold true for everybody. In fact, it might have a lot more to do with genes; one’s body’s ability to handle carbs, etc. I don’t know for sure, but it is interesting to think about these things.
To add to this comment more pertinent to this blog post here: The boys don’t have vegetable oils (other than olive oil – is that okay?), but will obviously ingest them at restaurants. They get plenty of saturated fats from the high meat diet we eat. They don’t consume much sugar at all and have always relied on Splenda for treats, which were sometimes plentiful and other times not. They are not big bread eaters, but do get their fair amount of wheat flour carbs, about 3 or 4 times a week. The boys eat fruit, but only in normal amounts and sometimes not even. They eat vegetables and sometimes not enough. They have taken vitamin supplements for years.
The ending of WW II brought with it some serious challenges for the carbohydrate based edible products industry. First, as shortages of meat and dairy products eased there was the tendency of people to return to their established habits, especially their former ways of eating. Having been deprived of a good steak or prime rib roast for a most of the war, many craved such foods. Food shortages and rationing were unpleasant, something most wished to relegate to a distant memory. The likelihood was that without good reason to do otherwise, people would start to revert to their old habits and, in so doing, reduce their consumption of carbohydrates to pre-war levels, something the carb based edible products industry would want to avoid for obvious reasons.
There was also the issue of a potential problem with the inclusion of a non-essential macronutrient in the RDA. This could be justified in times of shortages and the rationing of meat and dairy products. But justifying carbohydrate’s inclusion in the RDA in the absence of such shortages was another matter. Critics could draw attention to this discrepancy unless some compelling reason could be cited to validate the continued inclusion of carbohydrate in the RDA. Trying to rationalize the inclusion of carbohydrate without such a reason would only serve to draw attention to the obvious.
Then there was a problem with the “carbs are good for you” story. The very low carbohydrate diet that was part of the standard (and often very successful) treatment protocol for type II diabetics told a different story. If carbohydrates were “good for you”, why were they severely restricted for diabetics?
All these issues would have to be successfully addressed if the consumption of carbohydrates and carbohydrate based edible products were to increase, and they were.
Just had a couple of questions after reading this fascinating post.
1. Which fats do you recommend for cooking with? Which should be avoided? (Feel free to plug your book if the subject is covered).
2. What role has addiction played in the massive shift towards unhealthier diet over the past four decades? I know people who have had a ton of success with Atkins for a time, go off the wagon, and are never able to get back on track despite numerous short-lived attempts. I know people who talk about carbs in much the same way smokers talk about cigarrettes or alcoholics talk about drinking.
We use coconut oil and bacon grease to cook most of our stuff that requires cooking oil. If the temp isn’t too hot, we’ll occasionally use olive oil.
I do think there is an addictive component to carbs. Most people don’t miss them once they start on a good low-carb diet, but after falling away, they do seem to have difficulty getting back on a strict low-carb diet.
Hi. Does Intermittent Fasting reduce fatty liver? What’s the best way to burn off that fat for fuel?
Also, I’ll mention that I’ve never had grass fed beef but I have had wild venison. There is very little fat on it and what there is of it is tough and it tastes bad. So when I see people saying that they like the taste of grass fed beef, I wonder how much sleight of hand is involved on the part of the producers.
I would say that intermittent fasting would get rid of a fatty liver as long as one didn’t go hog wild on the carbs during the eating days.
Some people – my wife, for instance – love venison. I hate it. I love lamb; she hates it, especially if it smells at all lamby. I think it’s a matter of different taste preferences that different folks have more than malign intent on the part of the producers of grass-fed beef.
On the subject of fructose…I was surprised to read that you limit yourself to only around 3 gms/day! That would mean that you are restricting your consumption of fruits. I must admit that I’m somewhat surprised and amazed at how much negative publicity fructose has been receiving lately while being blamed for everything from the obesity epidemic to the reason why Bush invaded Iraq. ;0)
I’m aware that it is a type of sugar found mainly in fruits and that it requires metabolic processing in the liver, which is a big problem I take it. Studies out there have also suggested that consuming too much fructose messes up all kinds of things in the body — they show a correlation with obesity and tends to promote an increase in triglycerides in the blood, which of course are markers for heart disease. And as you’ve already implied…fructose can make the liver look like that of an alcoholic.
So seeing that fructose may be detrimental to one’s health, it would follow that our goal should be to reduce the fructose content as much as possible. But if you look at the % of fructose in some common fruits, compared to equal portions of sucrose, honey, and HFCS-55. (I’ve listed the total sugars in parentheses) you’ll notice something interesting:
Grapes: 42% (18)
Mangos: 54% (15)
Apples: 70% (13)
Strawberries: 52% (6)
Papaya: 60 (6)
Sucrose: 50% (100)
Honey: 53% (82)
HFCS-55: 55% (77)
Looking at those apples and papayas…one can see that they have a high % of fructose, higher even than honey, sugar, and HFCS-55. But does that mean they’re bad? I don’t believe so, especially if you were to look at the total amount of sugars per 100g, then couple that with some fiber, vitamins, minerals, and other goodies that you don’t get in other carbohydrate sources, and also contributing to bulk that limits how much you can eat.
So, I personally don’t feel that we should all get our panties in a twist over fructose thinking that it such an evil thing that we should limit it as much as possible, even if it means avoiding those fruits containing a lot of it. Hasn’t fruit been around for hundreds of thousands of years to nourish our Paleo ancestors? I will say with all due respect Dr. Mike, that I think fruit should not be avoided because of its fructose content, but should be eaten mainly as a dessert. We may need to watch the quantity because of the sugar content, but I sincerely don’t believe anyone is going to get fatty liver disease from eating apples, strawberries, etc.
On the subject of grass-fed beef…I just wanted to add another benefit to eating free-range beef and that is that the CLA content is found in much greater quantities as opposed to the amounts found in grain-fed beef. CLA has been reported in some studies to aid in weight-loss for some reason.
Sky King
The fruits that you find in the supermarkets today bear no resemblance to the fruits our Paleolithic ancestors had to eat. Large, juicy, sweet Washington Delicious apples didn’t exist 20,000 years ago. The apples that were around were little and gnarly. And your ancestors and mine had to fight the birds and the bugs for them during the brief time in the fall that they were ripe. The rest of the time there were no fruits, so although fruits have been around in some form for thousands of years, it ain’t in the form that you find it at Whole Foods today.
Although fruits contain a few vitamins and antioxidants, they are really not much better than candy due to their high sugar content. Sugar content not put there by nature, but by Luther Burbank and other folks who have developed hybrid fruits to fool the unwary into thinking they are eating health food.
Cheers–
MRE
You asked me to keep you updated on the weight loss, so even though comments are closed I’ll let you know anyway.
I started at 162 and am down 7.5 pounds to 154.5 in three weeks. I have even had some lapses such as a bowl of ice cream and some fruit that put me near 50 g. daily on a few days. Also, flavored coffee most days last week and I don’t have carbs for that but probably a no no. Still, good success and without weight lifting as my schedule is very busy right now. I could probably lose even faster if I really buckled down.
Over the past several years, I’ve gone from using canola oil to olive oil to now … bacon grease. I tried coconut oil, but hated the flavor, even though I bought the expensive expeller produced kind. The bacon grease lends a nice flavor to meats and even chicken.
Anyway, I make bacon maybe once every 8 to 12 weeks. I cook it in a frying pan over very low heat so that it doesn’t burn and stays nice and limp, but cooked, the way we like it. Does the fat still oxidize over low heat?
What do you think of my using the leftover bacon grease for cooking — like browning meat, etc.? I pour it into a ceramic dish and keep it covered in the fridge. It lasts for quite a long time (at least I use it for quite a long time, not sure if it actually “keeps” for that long).
Thoughts? Good, bad?
I’m intrigued by rendering lard (ala MD’s current blog). I tried it once, to very mediocre results. Maybe it’s time to try it again, if only I can find some good source for organic lard.
My thoughts on bacon grease are that it is good. We use it a lot.
MD has found a source for orgainic lard, which she listed in her blog post.
Cheers–
MRE
The ‘Age of Carbesity’
With the implementation of the RDA the world entered the ‘Age of Carbesity’ as defined by the new religion of the Church of Carbinology and the growing girth of its followers, the carbinists. Carbinologists toiled endlessly to find a process by which cholesterol could be rendered into gold through the art, which came to be known as Statinology. And lo and behold their efforts bore fruit in abundance and the Statinators went forth with their wares. And big pharma was pleased.
Meanwhile, the High Priests of Carbinology ordained thousands of upon thousands of certified nutritionists and dieticians as ‘Carbinators’ and bade them to go forth to spread the gospel according to the scriptures of the RDA, of the good that would come to those who consumed of the carb and the evil that would befall those who indulged in the fat of the land and the excesses of cholesterol as well as the evils of those who preached of the teachings of Atkinsinism.
The Carbamarketers looked over all this. They saw that it was good. And they gloated at their skills of their deception for having fooled so many who thought themselves to be wise. For the Carbamarketers knew full well that it was through their sleight of hand brilliance that the lowly carb had been vaulted from obscurity to a place of prominence in contemporary nutrition and, in so doing, they had overcome the limits of non-essentiality. The Carbamarketers had removed science from nutrition and installed religion in its place. And they saw that it was good. And they rejoiced.
I picked up a copy of “Protein Power,” copyright 1996, by Michael R. Eades, M.D. Thank you, Cheerwino, for the recommendation to read “The Protein Power Lifeplan” that was published years later.
From the reading of “Protein Power,” I was wondering if the author’s thoughts on various topics evolved over the years. For example, the author recommends “Beta-carotene (for vitamin A) 25,000 IU.” This is under the category of “In Search of an Excellent Vitamin and Mineral Supplement.”
My education is in clinical dietetics (B.S.) and in human performance and nutrition (M.Ed.). My job (funded by the USDA) is to counsel women during and after pregnancy, including how to feed their infants and children (WIC). My “expertise” in nutrition does not include the nutritional approach to fat loss as advocated by our host, Michael Eades, M.D. – a more-and-more useful field of expertise.
So, when Dr. Eades ventures from weight-loss (“fat loss”) to an area of nutrition science where I have more insight, I wonder how his knowledge has evolved.
None of us knew in 1996 that Beta-carotene in supplements, and added to foods, would ‘perform’ adversely in studies on cancer and heart disease. The recommendation now is to consume carotenoids (not just Beta-carotene) naturally from foods (as opposed to artificially from chemical companies, e.g., DSM and BASF, in the form of vitamin supplements), as carotenoids seem to work together as a team to prevent cancer and heart disease, whereas too much Beta-carotene interferes with the “teamwork” – increasing the incidence of oxidative and inflammatory diseases.
I am used to categorizing people nutritionally: athletes, pregnant women, infants, elderly, and so forth. Obviously, a patient in the “burn ward” has different nutritional needs than a patient with end-stage renal disease. I respect the fact Dr. Eades knows as much or more about these different sub-populations, in terms of their nutritional needs, as I. “Protein Power” is directed at a very specific sub-population – those who need to lose and to prevent excess body fat.
My interests recognize that particular need, but I am also interested in studying how concepts in “Protein Power” are (or are not) useful to health apart from fat loss.
The USDA’s stance on this sub-population (people in need of fat loss) is to advocate eating a diet based on the food pyramid and increasing physical activity (known as “Eat Smart / Move More”).
We (public nutritionists) are against low-carb diets for at least two “scientifically-based” reasons: 1. The Glycemic index is commonly misunderstood and misused for diet books, e.g., The South Beach Diet (most people do not eat two-cups of a single food after fasting, so why eliminate nutrient-dense foods from our diets based on this index?); and, 2. The low-carb diet is relatively high in saturated fat and cholesterol – “killers.” So, upon this “scientific knowledge” we recite “Eat Smart / Move More” to everyone who insists on talking about “losing weight” (not a public-health nutritionist’s favorite topic, I can tell you).
I agree the Glycemic index is misapplied.
I agree with Dr. Eades – the goal is not to lose weight, but to lose fat. I also agree the cholesterol concern is misgiven, and probably for the worst possible reason – the ties between “researchers” at the NIH and the drug companies that manufacture statins.
Knowing nutrition as it pertains to human performance, I am amazed at how most nutritionists remain on the anti-cholesterol bandwagon by failing and refusing to analyze this issue independently. I do not laugh at the number of people who stopped eating eggs and dairy products, since this tragedy outweighed the humor (e.g., trans-fat margarines).
My physician tells me I have a 1% chance of heart disease, based on my activity level, family history, lab results, EKG, BMI, blood pressure and on other data (but not based on a review of my diet).
Most of my calories are from complex carbohydrates, followed by fats and then proteins (I don’t drink – alcohol is readily converted to uric acid).
I don’t eat beef or pork. I am against the conditions under which too many of these animals are subjected. I only eat out once or twice a year and I’m too lazy to cook chicken.
Fish, dairy products (1% milk, cheeses and non-fat yogurt), eggs and beans are my protein sources.
I find my knowledge evolving. Stephen J. Barrett, M.D., posted a statement on low-carb diets on his Quackwatch website. Based on various studies, he acknowledged low-carb diets are an acceptable option for weight loss for a sub-population of people. His reputation and his position on low-carb diets inspire me to keep an open mind and to learn more.
The anti-inflammatory and anti-oxidative properties of foods are more likely to help prevent heart diseases and cancers than the concept of “fats versus carbohydrates.”
So, is Omega-3 superior to saturated fat as an anti-inflammatory agent? Are saturated fats less oxidative than PUFA in vitro (PUFA’s, e.g., Omega-3 fatty acids, are escorted by tocopherols)?
In “Protein Power,” the idea is to limit carbohydrates (30 grams / 120-calories per day in “Phase I”) and limit protein (~ 72 grams / 288-calories for me per day), but “don’t worry” about such limitations for fat, except to choose “healthy fats”: “olive oil, nut oils, avocado, and butter.”
This daily diet is equivalent to about one slice of bread and 12 large eggs. (Vasily Alekseyev, who set 80 world records in weight lifting in the 1970’s, ate a 36-egg omelet each breakfast when weight-lift training. Yet, he still lives…)
Well, if my energy demand for a given day is 2,400 calories, then I would need an addition 221 grams of fat to maintain my weight. That’s ~ 16 tablespoons of those “healthy fats” listed above. So, one slice of bread, 12 large eggs and 16 tablespoons of “healthy fats” (“good eicosanoids”) per day in “Phase I.”
I’m already glad I don’t need to lose fat. But, I recognize many people do have this need.
The first question I need to answer before I present “Protein Power” as an option for certain patients to discuss with their physicians is on how fat is metabolized in the absence of insulin.
I cannot agree complex carbohydrates are “bad.” Can we agree any energy is “good,” so long as: 1. Energy intake does not exceed total energy demand; and, 2. The specific energy source, e.g., strawberries, does not promote oxidative damage and promote inflammation?
Fats enter fat cells with insulin, but fats enter non-fat cells without insulin (how could fats be useful to us on the “Protein Power” diet if not?). Even if fats could not enter non-fat cells without insulin, then would we want excess fat remaining in our blood (increasing blood viscosity, etc.)?
This is the heart of my concern – If excess calories are not stored as triglycerides in fat cells via insulin, then … where are excess calories going? (This is not an issue if there are no excess calories. But, “Protein Power” tells us “don’t worry” [about the amount of fat intake].)
Dr. Eades promotes exercise (“weight-lifting is best”). If a person loses fat with this diet and exercise (not just loses “weight,” e.g., dehydration), then the fat is being used aerobically for energy. (Only carbohydrates are used for anaerobic exercise.) In this case, fats would not pose a risk to organ function, as the fat is entering muscle cells to do work without insulin.
But if a person does not lose weight on the “Protein Power” diet, then I would “worry” there is too little exercise and too much fat intake, and the fats may be entering non-fat cells without insulin which could pose a risk to organ function. My plan is to study this concern. Perhaps I will find where Dr. Eades already addressed this issue.
In the meantime, posts here about – “fats good, carbohydrates bad” – while neglecting to mention exercise – concern me. Speaking for all nutritionists, we do not like the hopeless quest to be fit by dieting without exercise. Dieting without exercise is not what Dr. Eades is prescribing, so why not post comments discussing our exercise habits, too?
I exercise daily, but thanks to my car, my desk job, my local grocery store and so forth I doubt I get half the physical activity as my “Paleolithic ancestors.” So, why eat like them if we’re not going to move (and migrate) like them?
Without the exercise Dr. Eades recommends, I cannot imagine any diet building muscle tissue or bone density, with or without carbohydrates and insulin.
Thank you for providing this opportunity to learn more about healthful fat loss by decreasing carbohydrates, calculating protein intake, unmeasured fat intake (“good eicosanoids”) and with exercise.
“But the exercise must be strenuous and done until muscle exhaustion almost to the point of failure for maximum results” – “Protein Power,” page 192.
I’ll keep reading…
Zach
Carbohydrate became part of the recommended daily allowance (RDA) in 1941 but in an indirect manner. The RDA contained a requirement for energy and protein. It specified the amount of protein required but noted that the recommended amount represented a small percentage of a person’s energy allowance. The remainder of the energy allowance was to be acquired from carbohydrates and fats. The general guideline for carbohydrate and fat is that more than half (i.e. more than 50%) of daily energy should come from carbohydrates, with no more than one-third (i.e. 33%) from fat. This was a back door way of making carbohydrate appear to be an important nutrient without running headlong into the non-essential nutrient issue.
It was also a back door way of invalidating a restricted or low carbohydrate diet with in many cases is less than 5% of the total energy requirements. Since carbohydrate restriction goes hand in hand with a high fat intake the RDA energy recommendation limiting fat intake caught the carb restricted diet in a pincer vise.
The inclusion and prominence of carbohydrates in the Food Guide is an important issue because carbohydrate is a non-essential nutrient. As far as I have been able to ascertain the fact that no requirement in human nutrition has been identified for carbohydrate has never been indicated with recommendations for the allowance for this macro nutrient.
The above issues raise the question of whether the campaign against fat and cholesterol has its roots in a program to promote carbohydrate consumption.
Superior Nutrition
The RDA was touted providing superior nutrition as based on the input of experts. Superior nutrition according to the RDA was a diet high in carbohydrates and low in fat. “More than half” (of the energy allowance), as applied to carbohydrate, implied that a diet would be the most superior if all the energy allowance remaining after deducting protein’s contribution came from carbohydrate. “No more than one-third”, as applied to fat, implied that a diet with less fat was better and that a diet with zero fat was most superior.
There was one more neat little trick in the RDA. Grouping fat and carbohydrate under the term ‘energy’ put them on the same level. That fat was an essential nutrient and carbohydrate was not was not necessary to mention once they were both reduced to ‘energy’. Giving carbohydrate almost twice the energy allowance of fat implied that carbohydrate was a superior nutrient.
The message in the RDA was clear; maximize carbohydrate and minimize fat intake. The RDA also implied that this relationship was based on science which it clearly was not.
In the early 1950s the RDA was revised to include the serving concept. This further drove home the message to eat one’s carbs and minimize or avoid fat.
It was also about this time that Keys started his campaign against cholesterol and fat which coincidently just happened to support the recommendations of the RDA.
Hi Dr. Eades: Great Picture – especially the real butter on top of the steak. Meals like that have hleped me keep my weight off and heart healthy, AND have helped my wife maintain sanity as a type 1 diabetic. Scary thing is that if the American Diabetes Association had their way, this would be our dinner tonight!
http://www.diabetes.org/recipeoftheday.jsp?WTLPromo=HOME_rotd&vms=272459344953
Thanks again,
David and Susan Futoma
PS: I have the same weakness for fresh summertime tomatoes as well, despite some carbs!
Very few carbs in the summertime tomatoes.
Did the RDA (which was formulated based on considerations of rationing and the shortage of certain foods) and the K-Ration of the early forties change the way we eat? According to this article they did exactly that and in a big way. The K-Ration and RDA changed the ‘business of farming’ too. In what way did the business of farming change? Read on.
Changes in Eating Habits
During the war rationing at home and K-rations abroad changed the eating habits of Americans and changed the business of farming.
http://www.livinghistoryfarm.org/farminginthe40s/life_24.html
According to the article here are a few of the new foods that were first produced and sold in the 1940s.
* Mrs. Paul’s frozen fish sticks
* Cheerios (first sold as Cheeri Oats, the first read-to-eat oat
cereal) and Kellogg’s Raisin Bran
* Minute Rice
* Reddi-Whip whipped cream
* Nestles Quick powdered drink mix
* Packaged cake mixes
* M&Ms Chocolate Candies, Peppermint Patty, Junior Mints, Almond
Joy, Whoppers malted milk balls, Jolly Rancher Candies
* Deep Dish Pizza (Pizzeria Uno, Chicago)
Looks like the beginnings of carbohydrate revolution to me. Does this give anyone an idea of how the nature of farming changed? Back in the days before the RDA and K-Ration, most people bought everything they needed for their meals from a corner grocery store, a vegetable stand, a butcher shop and perhaps a fish monger. That was in the pre-carbinean era. Today, thanks to carb based manufactured edible products, we have huge super markets with thousands of new pseudo foods – all made possible because of the events of WW II.
On the question of fructose and fruit, the mountain of money that found its way into cardiovascular disease research in the 70s and 80s has recently had some side benefits for cancer research.
A clear association has been established between insulin resistance and cardiovascular disease as a result of the Insulin Resistance Atherosclerosis Study (funded by the successor to the National Heart Institute, the National Heart, Lung and Blood Institute) conducted in the US in the early 90s.
In-depth analysis in 2003 of the response to questionnaires from that study by researchers from the Department of Epidemiology (medical statistics) at the Universities of South Carolina, Minnesota and Wake Forest confirmed the subsidiary conclusion from the original study, that fibre increases insulin sensitivity. This means that the fibre in fruit appears to have a protective effect against the lipid production caused by the fructose in the fruit. So perhaps fruit is only bad for us when we eat the fructose and throw away the fibre (also known as fruit juice).
I’m not so sure that fiber is the magic substance many people think it is. It does reduce the rate at which sugars absorb, but I can’t see how it could affect insulin sensitivity. It can, however, cause damage to the GI tract.