Archive for November, 2005
In the study, 17ß-Estradiol Supplementation Decreases Glucose Rate of Appearance and Disappearance with No Effect on Glycogen Utilization during Moderate Intensity Exercise in Men, conducted by research teams from McMaster University and University of Geulph (both in Ontario, Canada), researchers set out to see if the hormone estrogen influences substrate (fat or glucose) selection for energy.
In a randomized, double-blind, placebo-controlled setting researchers investigated whether supplementation of estrogen given to men would effect glucose turnover and net muscle glycogen in eleven men over a period of eight days.
The result was intriging.
With estrogen supplementation, the fuel selection of the men was altered – to an increase in lipid use with a reduction in carbohydrate use. Alos, a reduction in glucose rate of appearance, primarily in the liver, and a reduction in glucose rate of disappearance, primarily in muscle uptake, was also noted. One last important finding was in the basal level of total muscle glycogen in study subjects – it was reduced.
Now the good part – what this all means and the reason for my headline.
While the study was done on male subjects, these results suggest that women are designed to have a preference to burn fat for energy – estrogen stimulates and influences the substrate preference for fat. It also helps to explain why women often have a hard time losing weight – especially when they eat a higher carb diet – and why they so easily gain weight when they eat excessive carbohydrate in their diet.
Quite simply, it is how their bodies are designed to work with their estrogen.
As this study demonstrates, estrogen stimulates the selection of fat for energy. But, if the right fuel is not eaten, the body is at a disadvantage for energy selection and use – I’ve said this many times before, that it is important to provide the body with the right fuel!
For women, that fuel is preferentially fat and a higher carbohydrate diet will inhibit this. A reduction in carbohydrate with adequate protein and fat in the diet will make all the difference. It’s called controlled-carb nutrition and it works to bring that balance of fuel for energy, especially for women.
Yesterday New Scientist had a fascinating article, The food you eat may change your genes for life, that adds one more perspective to the article I wrote about Gerald Shulman’s research findings, Insulin Resistance In Your Cells?
In my previous article I talked about the critical importance of nutrients in our diet – and we get those nutrients from our food. This new article highlights the importance of the food we eat in our health and how the wrong food can mean long-term damage to our genes, sometimes even before we’re born.
The article begins with a review of previous research into environmental factors that influence gene expression – in mice and rats – such as foods eaten by pregnant pups and the outcome of offspring and the care of the offspring, neglect or cared for. In new research, the team of researchers showed that a food supplement can have the same effect on well-reared rats at 90 days old – well into adulthood – as neglectful care did in previous research.
The researchers injected L-methionine, a common amino acid and food supplement, into the brains of well-reared rats. The amino acid methylated the glucocorticoid gene, and the animals’ behaviour changed. “They were almost exactly like the poorly raised group,” says Szyf, who announced his findings at a small meeting on environmental epigenomics earlier this month in Durham, North Carolina.
The researchers believe the reverse may also be true since other research has shown that poorly raised rats – those “stressed” and behaving badly – have been successfully “reversed” to more normal behavior using a chemical called TSA.
Rob Waterland from Baylor College of Medicine in Houston, Texas…says Szyf’s ideas are creating a buzz, as they suggest that methylation can influence our DNA well into adulthood. A huge number of diseases are caused by changes to how our DNA is expressed, and this opens up new ways of thinking about how to prevent and treat them, he says.
Indeed it does, and on a more fundamental level than just behavior, but on our health! When we eat the “right” foods – that is those that provide our essential nutrients – we are providing the critical things our body needs to function. When we fill our body with non-nutritive things, like trans-fats, high fructose corn syrup, preservatives or chemicals, we’re doing the opposite – we’re robbing our body of its ability to thrive.
Yes, it will still function, but that function will be impaired – even if we don’t feel it happening at first – and create problems over time. Which brings the question – can such damage be reversed? Can we undo years of poor eating habits?
In my opinion, the vast majority of damage caused by a poor diet can be reversed – it takes time, but the body has an amazing ability to heal itself when given the right tools. Those tools are nutrients, and those we get from our food. Choose the right foods and stay away from those foods that are harmful to health and your body can heal itself in time. And, even if the damage doesn’t completely reverse, at least you know you’re not doing more damage in the long term when you do modify your diet to be nutrient-dense.
MedPage Today reported yesterday on new findings from researchers at Yale – Insulin Resistance may be an inherited condition due to reduced mitochondrial activity in muscle cells in the children of those with Type II Diabetes.
That, the researchers said, can lead to insulin resistance even when the progeny are young, lean, and have normal glucose levels.
The finding adds to the weight of evidence suggesting that mitochondrial dysfunction in insulin-resistance pathways may play a major role in the development of type 2 diabetes, suggested endocrinologist Gerald I. Shulman, M.D., Ph.D., a Howard Hughes Medical Institute Investigator at Yale and colleagues at Children’s Hospital Boston.
The researchers believe these new findings may provide new insights into possible defects that may be responsible or contribute to the development of Type II Diabetes.
“These data support the hypothesis that reductions in mitochondrial content are at least in part responsible for the reduced mitochondrial activity that has previously been described in insulin-resistant offspring.”
The changes they detected were independent of changes in other key transcriptional factors and co-regulators of mitochondrial development, they added.
In my mind, this type of research is so important – it underscores the critical need for a nutrient-dense, “real food” diet, especially in pregnant women. From well before we are born until the day we die, our nutrient requirements are fixed – we need essential nutrients to grow, develop, thrive, repair and build cells – without them we are functioning at a less than optimal level and when one is pregnant and not eating a nutrient-dense diet, providing less of the critical “building blocks” for the development of the fetus.
Over time, research such as this, is going to lead to radical changes in our dietary recommendations as our understanding grows even more. Throughout various periods in our life our nutrient requirements change – sometimes we need more fat, sometimes we need more protein – and as we hone in on these changing requirements, our dietary recommendations will develop to be more individualized than we see today.
I also believe that this type of research is going to contribute to the growing area of nutrition based on genetics – perhaps in the future we will see a test of some sort that can provide details to an individual about their genetic predispositions so their diet is tailored to their individual needs from a genetic and cellular level? Ahh, what the future holds for us!
Of note, Dr. Shulman is scheduled to present research findings at the upcoming Nutritional and Metabolic Aspects of Carbohydrate Restriction conference in January about his research in the area of “Insulin Resistance and Inflammation.”
Score one more for controlled-carb nutrition!
Forbes today reported research findings that show that two carbohydrate-restricted versions of the government’s Dietary Approaches to Stop Hypertention (DASH) Diet had beneficial effects on blood pressure, cholesterol levels and long-term cardiovascular risk.
The new diet shifts about 10 percent of calories from carbohydrates to either protein-rich foods or to monounsaturated fats such as olive or canola oil.
“This is a modified version of the old diet,” [Dr. Frank] Sacks explained. “The DASH diet was a real breakthrough for lowering blood pressure and we changed it. We reduced the carbohydrate content and replaced it with unsaturated fat or protein, and it lowered blood pressure more and improved lipids, and overall cardiovascular risk goes down.”
For this study, 164 adults aged 30 and older with elevated blood pressure were assigned to one of three diets: one in which carbohydrates represented 55 percent of calories (close to the original DASH diet); one that shifted 10 percent of carbohydrate calories to protein (about two-thirds from plant sources and the rest from chicken and egg whites); and one that shifted 10 percent of calories to unsaturated fat, mostly olive or canola oils.
What the researchers found was that all participants had some improvements – but those following the diet that reduced carbohydrate saw significantly better improvement. What’s more – those on the controlled-carb regiments reduced their cardiovascular risk more than those following the traditional DASH Diet.
With all the continuing evidence that reducing carbohydrate in the diet leads to improvements in health, it makes me wonder why there remains such resistance in the scientific and medical communities to accept the obvious?
As a nation we jumped head-long into the theory of low-fat diets and still continue to perpetrate the myth that low-fat is healthier for everyone.
I’ve said it before, and I’ll say it again – for some individualas, a low-fat diet may indeed be better. But, the evidence is clear that a low-fat approach may also be damaging to the health of other individuals. For those individuals not well-suited metabolically to a low-fat approach, a controlled-carb approach is often a healthier option – an option that must be added to the “toolbox” of options physicians recommend to their patients if/when a low-fat approach is clearly not working or even worsening an individuals health.
Today, in the journal Nutrition & Metabolism, researchers published findings that can only be considered one of those rare moments in scientific discovery – Carbohydrate restriction improves the features of Metabolic Syndrome. Metabolic Syndrome may be defined by the response to carbohydrate restriction.
In a review of the medical literature about low-carb diets, researchers found something that’s been there, in the published data, all along – the list of things carbohydrate restriction improves happens to be the same list of features a patient presents with in the diagnosis of Metabolic Syndrome, a cluster of metabolic markers that increase the risk of diabetes, stroke and heart disease: obesity, high triglycerides, low HDL (“good” cholesterol), high blood sugar, high blood pressure and insulin resistance.
“It’s been staring us in the face for years,” said Dr. Richard Feinman, PhD, of SUNY Downstate. “Now we’ve connected the dots.”
Now that may not seem like much, but when you consider that in recent months there has been dissent and question about the definition, diagnosis and treatment of Metabolic Syndrome, from some of the leading medical organizations, this is a big deal.
As Jeff Volek, PhD, RD, lead researcher from the University of Connecticut, Storrs said, “Make a list of the features of metabolic syndrome, then, make a list of the things that carbohydrate restriction is good at fixing. They’re the same list. Somehow, we never really noticed that. We know the cause of metabolic syndrome is often linked to disruption of insulin. Thus, the key to treating metabolic syndrome is to control insulin, and carbohydrates are the major stimulus for insulin.”
The findings of this study should help in establishing a firm diagnosis criteria with observation of the impact carbohydrate restriction has on the markers of Metabolic Syndrome in an individual already diagnoised or suspected of having the disorder. This is a ground-breaking, evidence-based approach that could radically change how the estimated 25% of Americans with Metabolic Syndrome have their symptoms managed and treated!
Often those with the features of Metabolic Syndrome are told to follow a low-fat diet in the course of managing the different markers of the disorder. But, as this study points out, data from published studies shows that low-fat diets often worsen the features of Metabolic Syndrome. The key in these new findings is that fat intake is less of an issue than reducing carbohydrate intake and that how a person responds to carbohydrate restriction may actually be a critical key to diagnose Metabolic Syndrome.
Basically, if a dietary intervention is tried and it restricts carbohydrate wihtout restricting fat and that leads to improvements of the features of Metabolic Syndrome, than that may be the right dietary approach for that person. Too often these days when one is trying to reduce their carbohydrate intake, they also try to limit their fat intake, which makes following a reduced carbohydrate diet difficult.
These findings show that fat intake is less important when a person has Metabolic Syndrome – that the carbohydrate is the key, not the fat in their diet. As Dr. Feinman pointed out, “The most obvious factor in the obesity epidemic is the drastic increase in carbohydrate consumption in recent years and the decrease in fat consumption, so the story is consistent. I think people have learned the value of reducing carbohydrates during the media popularization of low-carb diets, but they are still making it hard for themselves by also trying to reduce fat, when fat seems to be much less important a factor than carbohydrates.”
This article highlights how even those of us who have been deeply involved with controlled carbohydrate nutrition have missed the forest for the trees about just how appropriate a low-carb diet may be for some – when I first read through the paper, my first reaction was “oh yeah – well, duh!” – because it is so obvious, yet until now was not out there, in full view, as it is today.
Dr. Feinman and Dr. Volek, in addition to being co-authors of this paper, are also organizers of the upcoming conference, Nutritional & Metabolic Aspects of Carbohydrate Restriction 2006, in Brooklyn, New York – January 20-22, 2006. For anyone who is interested in nutrition, metabolism, diet and health, this is a must attend conference – there will be three dozen speakers, presenting data from studies across the spectrum of controlled-carb nutrition, many coming from around the world to speak.
Of particular interest to those with Metabolic Syndrome, or phyisicans and other healthcare professionals working with those who have Metabolic Syndrome, will be presentations from Dr. Gerald Shulman from Yale University, Dr. Marc Hellerstein from University of California, Berkeley, Dr. Marcus Stoffel from Rockefeller University, and Dr. Jeff Volek from UConn, Storrs.
Yesterday the Daily Mail included an article, Eight factors for childhood obesity, that detailed the findings from a recent study published in the British Journal of Medicine. The study “involved 8,234 youngsters aged seven, plus a further sample of 909 children who were taking part in a large UK study. The children’s height and weight were measured and their body mass index – a measure of weight in relation to height – was calculated. The researchers then considered a range of factors which might increase the risk of obesity.”
The findings included the following factors that correlated with an increased risk of obesity by age seven:
- Birth weight
- Obesity in one or both parents
- More than eight hours spent watching TV a week at the age of three
- A short amount of sleep – less than 10.5 hours a night at the age of three
- Size in early life – measured at eight and 18 months
- Rapid weight gain in the first year of life
- Rapid catch-up growth between birth and two years of age
- Early development of body fatness in pre-school years – before the age at which body fat should be increasing (at the age of 5-6)
Have you seen how kids eat today?
Why is diet – what is probably the biggest influence in risk of obesity – not on the list?
It most certainly is a factor – a big one at that. We know this.
Yet, it is not included here.
With the exception, perhaps, of time spent watching television, every factor listed is closely tied to diet – and the case can even be made that links more television time to diet with that additional time spent watching television providing more time to snack in front of the TV.
I don’t know how overall diet – foods eaten, quality of those foods, nutrient-density of the diet – failed to make the list. So, here I’m saying it – a nutritionally bankrupt diet in childhood is a significant risk factor for obesity.
Children eat what we feed them – they are not “decision makers” about their diet. If they’re offered french fries and soda – guess what? – they’re going to consume them willingly. If they’re offered instead broccoli florets with dip and water, they might not be all that happy initially with the change, but if they’re hungry, they’ll consume them willingly too.
When I’m out with my son, who is just 14-months old, I can’t tell you how often his eating habits draw the attention of nearby parents who also have small children. Just last week we were shopping at the nearby mall and stopped in the food court for a bite to eat.
Now you may be thinking – the food court? – what could she have possibly found that was not junk food at the food court?
Two quick stops was all it took. First the barbque place for a side of vegetables – the steamed broccoli, red peppers, onions and green beans looked good. Second stop, the salad place for a grilled chicken caesar salad sans the croutons and a bottle of spring water.
At our table, as my son feasted on grilled chicken breast, broccoli, red peppers and green beans along with enjoying his sippy cup of water, and I was enjoying my salad and the remaining chicken, another mom sitting at the next table with her toddler commented that “wow, my son will only eat french fries” as she handed him another one.
For me, moments like this are opportunities – not for judgement, but for education.
So I said that the easiest way to get a child to eat vegetables and things like chicken is to only offer those foods. That her son might protest at first, which is understandable, but she might want to try it and see since I thought she might be surprised how quickly her son will adapt to the change – children of that age simply won’t starve themselves, at some point, when they’re hungry they will eat the food you give them, even when it’s not french fries.
I often write here in my blog about ways parents can make changes in their childrens’ diet because it really is so important. Our children are the future and we’re letting them down every time we capitulate to what has become “normal” in society – fast food dinners, quick stops at the mini-mart for sodas, packaged processed foods making up the majority of our diet.
This radical change in our eating habits is less than one generation old – most under 30-year-olds will be hard pressed to remember eating out as frequently, eating as much fast food, eating processed & packaged foods as staples, snacking as frequently, drinking as much soda and sweetened beverages, consuming as much junk food, and eating in cars as much as we do today.
Yet, many accept – dare I say, embrace – the changes as normal and even needed in our fast-paced society. As adults we’ve changed how we eat – for the worse – and we’re passing these bad habits to children younger and younger each year.
Too many do not cringe when they see a toddler with a baby bottle filled with soda, instead it’s seen as cute.
Too many are not alarmed when a baby is given french fries at the local fast food restaurant, instead it’s viewed as giving the baby a “vegetable” and not a food devoid of nutritional value that may be harmful given the fact it contains damaged fats and/or trans-fats.
Too many are quick to give small children bites of donuts, cookies and candy because that’s what they’re snacking on and the child wants some too.
Today we even buy stollers, car seats and other children’s items with built in cup holders and feeding trays! What message is this sending babies and small children?
For those who read this who are parents, or may soon be parents, please think about your child’s future and how the decisions you make about what and how you feed your child will have a lasting impact on their health and well-being in the long-term! You are the “decision maker” about what your child eats – use that power of influence and position of authority early and often while they’re young to ensure they eat a nutrient-dense diet that is rich with vegetables and other good, nutritious food instead of worthless junk food.