Lots of Links

Can running help with skin conditions? And more evidence of the less is more approach to running.

The mainstream media is picking up on the increasing evidence that its the increase of sugar in our diet that has caused the obesity crisis. Its been posted everywhere, so I won’t comment much – low-carb diet came out best for longterm weight loss. But before you get too concerned, being skinny is more of a health risk than being moderately overweight.

Keep exercising! The evidence is mounting up that regular intensive exercise can keep your body performing like a much younger person (maybe not the fittest younger person, but still!). And if you’re afraid of the chronic cardio argument (or using it as an excuse) Jason Fitzgerald takes on the arguments against running. If you can – run outside. Running outside offers mental health benefits that running in a gym doesn’t. Don’t forget to strengthen as well as stretch to prevent ITB.

A comprehensive look at the dangers of phytoestrogens and why you should limit your soy intake.

Eating lowfat salad dressing decreases your ability to absorb nutrients from your salad.

It seems getting people to reduce their meat consumptions isn’t the ecological saviour to the planet that some people have (ardently) proposed. On the subject of unverified claims – it seems the danger of drinking while pregnant has been overstated. Fetal alcohol syndrome is real, but there’s no evidence that light or moderate drinking is implicated.

And the biggest news for all those interested in scientifically verified health news – British scientific research is to be made publically available within five years!

The wonderful web – a week of links

What a week of interesting stories:

As a long time user of lip balms and lipstick, I’ve heard the complaints – lip balm is addictive. Its seems the answer is maybe psychologically.

Opt for a plain balm with a petrolatum, beeswax, or oil-based lubricating cream, and avoid lip products that contain chemicals such as menthol, camphor, or phenol (they may irritate skin more!). One final piece of advice: Be sure to apply balm only when lips are chapped— normal lips don’t necessarily need extra moisture! One study found that when moisturizers were used on normal (a.k.a. not dry) skin, it increased skin susceptibility to irritants ^{[3] [4]}. If lips aren’t normally chapped, it may be better not to start applying lip balm at all

Conditioning Research posts on the increasing evidence linking sleep deprivation and obesity:

Observational studies have observed cross-sectional associations between short sleep duration (generally <6 h per night) and increased body mass index or obesity, prevalent diabetes, and prevalent hypertension. Some studies also reported an association between self-reported long sleep duration (generally >8 h per night) and cardiometabolic disease. A few prospective studies have found a significant increased risk of weight gain, incident diabetes, and incident hypertension associated with inadequate sleep.

While this is still to be understood, the assumption is that lack of sleep causes stress, and high cortisol levels are a cause of obesity. As some who has both struggled with insomnia and weight in the past, this is concerning – as it can become a vicious cycle. Part of my insomnia is related to restless leg syndrome and night cramps – something a paleo diet with magnesium supplements has helped alleviate. But then there are nights that you can’t turn your mind off. Seth’s blog has been running an ongoing look at the effects of Vitamin D3 supplementation and its role on sleep.

A month ago I blogged about a “stunning discovery”: Primal Girl’s sleep got much better when she took Vitamin D3 in the early morning instead of much later (afternoon or evening). Others pointed out a similar observation: Taking Vitamin D3 in the evening caused insomnia. These observations suggest that Vitamin D3 resembles sunlight in its effect on sleep: morning exposure good, evening exposure bad. Sunlight, of course, is hard to control and sometimes hard to get (which is why Primal Girl tried Vitamin D3). Sunlight is also time-consuming: it takes an hour to get one hour of sunlight. The timing and dosage of Vitamin D3 is much easier to control.

And its starting to look like the need for Vitamin D is becoming part of mainstream health attitudes (or re-becoming).

When I started looking into being healthy agave nectar featured as a healthy natural sweetener. From a vegan perspective, its also considered a good one (though it falls under the we ignore the damage it causes being harvested/grown as long as it doesn’t come directly from an animal). Food renegade looks at how unnatural, processed and unhealthy agave nectar is.

Native Mexican peoples do make a sort of sweetener out of the agave plant. It’s called miel de agave, and it’s made by boiling the agave sap for a couple of hours. Think of it as the Mexican version of authentic Canadian maple syrup. … Agave nectar is not traditional, is highly refined, and actually has more concentrated fructose than high-fructose corn syrup. It is not a “natural” sweetener. … Concentrated fructose is not found in fruit, or anywhere else in nature. When the sugar occurs in nature, it is often called “levulose” and is accompanied by naturally-occurring enzymes, vitamins, minerals, fiber, and fruit pectin.  Concentrated fructose, on the other hand, is a man-made sugar created by the refining process.

The importance of removing gluten from the diet is hitting mainstream awareness even if there still is a sense that we should  be eating grains so the real problem with avoiding gluten is missing out. There’s no scientific reason to say people have to eat grains. I realise this is still a new area of study and we don’t have proof of non-coelieac gluten intolerance.

Improvements to a person’s health without gluten can be explained several ways, by placebo effect or by the fact a gluten-free diet removes other agents from the body – most importantly the poorly absorbed carbohydrates known as fructans, which may cause illness or discomfit.

…

Penny Dellsperger, a dietitian at Coeliac NSW, said there were significant medical risks to people adopting gluten free diets without first ascertaining whether they suffered coeliac disease. She said the symptoms could easily relate to other illnesses.

That’s the only real risk – that people get enough improvement from removing grains that they assume that’s it rather than continuing to investigate the problem and miss another issue. But that doesn’t redeem gluten.

Of course, the anti-anti-gluten argument comes from the assumption that a low-carb diet is unhealthy. We need carbohydrates, yes but even the ketosis fans eat their vegetables. But compared to the pasta and bread folks, we’re all generally much lower carb. Stumptuous reports on studies showing the importance of eating quality protein sources. While Robert Paterson asks us to look at the whole animal before saying meat is too expensive.

But speaking of carbs – just how many do you need to fuel your endurance exercise? And Strength Running offers more guidance on protecting yourself while building endurance.

But before we finish, lets take a look at the charlatans out there. Vaccines are for prostitutes, according to one acupuncturist. I suppose when your entire field is based on magical thinking, things like cancer only happen to people you think deserve it. And more evidence that the cure is worse than the disease – at least when your cure is made up without evidence as is chiropractic treatments and yoga. Sure there’s a couple of thousand years between their invention, but they both still come from a far from scientific understanding of how the body works.

Link Roundup

Norway is suffering a butter shortage due to the popularity of low-carb diets.

Stevia wins European approval – in general I try to avoid artificial sweeteners but if its safe, more choice is good. Jezebel looks at the evils of pharmaceutical companies. And now another reason to doubt rice is the benign grain – arsenic!

More evidence emerges that eating fish is good for you: helping to prevent alzheimers; and the younger a baby is when it starts consuming fish, the less likely it is to suffer preschool wheeze.

Lifehacker looks at how to stop negative thoughts. Rob Wolf looks at how to identify if your cravings are due to biological, emotional or external triggers.

Evolutionary Psychology looks at depression and chemical imbalance. Wheat Belly author, Dr Davis is interviewed at Wellness Mama.

Mark’s Daily Apple looks at how to train for a marathon the healthy way – I’m hoping this will be useful at my planned half-marathon level. I’m really not wanting to go through the carb binge cycle like last time. And while I’m thinking about it, Strength Running takes a look at the real world benefits of endurance running.

The Netherlands wasn’t always a cyclist’s paradise – a look at the deliberate planning that went into improving the cycle-friendliness of Dutch cities. Lovely Bike argues against social ideas of female modesty limiting women’s ability to talk about their experiences.

Skeptic North takes aim at the poor arguments used against those sceptical of Big Nature.

Speaking of sceptical wins – the Burzynski Clinic‘s attempts to silence their critics has backfired. Now they’re  firing their thug…

Low-Carbohydrate and High Protein to slow Tumour Growth

A new study has been published providing evidence that a diet low in carbohydrates and high in protein may help slow tumour growth.

Our study, herein, shows that a high amylose containing low CHO, high protein diet reduces BG, insulin, and glycolysis, slows tumor growth, reduces tumor incidence, and works additively with existing therapies without weight loss or kidney failure. Such a diet, therefore, has the potential of being both a novel cancer prophylactic and treatment, warranting further investigation of its applicability in the clinic, especially in combination with existing therapies.

 

Previous studies have also suggested a link between a carbohydrate-rich diet and prostate cancer.

• A Low-carb Diet May Stunt Prostate Tumor Growth.
• Carbohydrate Restriction May Slow Prostate Tumor Growth.
• High Carb Diet Linked to Prostate Tumor Growth.

Do we start advocating the prostate cancer diet?

 

Ketogenic Low-Carbohydrate Diets have no Metabolic Advantage over Nonketogenic Low-carbohydrate diets | BodyRecomposition – The Home of Lyle McDonald

There’s a to advocate a low-carbohydrate diet. The most calorie dense carbohydrates tend to come from grains. While the paleo crowd have arguments about the dangers of grains in terms of gluten and lectins, from a purely weight-loss point of view, grains are calorie-dense and nutrient poor. Removing dense carbohydrates from the diet (and depending on the approach can include fruits, potatoes and other starchy vegetables) certainly frees up a lot of calories that can be used to bulk up the meal – leafy vegetables and meats and fats.

There is also the argument against carbohydrates as outlined in by Gary Taubes : Outline here that looks at the health issues caused by spiking our blood sugar levels. Unfortunately this tends to fall by the wayside and the reason most people hear about low-carb diets is the weight-loss side – or more specifically fat loss.

This is where the debate gets more complicated over how far to cut back. Do you need to go to a ketogenic diet in order to get the advantage of low-carb? A new study suggests not:

Ketogenic Low-Carbohydrate Diets have no Metabolic Advantage over Nonketogenic Low-carbohydrate diets

In terms of weight and fat loss, at the end of 6 weeks both groups had lost roughly the same amount of weight (6.3kg for the ketogenic diet, and 7.2 kg for the non-ketogenic diet; this was not statistically significant).  As well, the loss of body fat was the same (3.4 kg in the ketogenic diet and 5.5 kg in the non-ketogenic diet; again this was not statistically different even if the non-ketogenic diet seems to have lost ~4 pounds more fat).  There was no significant change in fat free mass for either diet.

You could argue that ketogenic diets make things simpler – but if you’ve ever looked on a  message board as people discuss the merits of one or two grams of carbs, you might doubt that. However, I appreciate that the internet is the place for that kind of nerdery and you can get a false idea of its complexity based on people having fun with that kind of detail. Personally – I prefer eating some carbohydrates. I’ve adjusted enough that I think of bread, pasta and rice as cheating along with more standard cakes, chips etc. But I’m at a point where I don’t want to be not adding a zuccini to my stirfry because of the the carbs.

Hunger ratings improved for both diets with no difference between diets.  An oft-heard claim is that ketogenic diets cause hunger blunting due to the presence of ketones or what have you; but this study does not support that.  Given that protein is the most filling nutrient, the effect seems to be mediated by the increased protein content, not decreasing carbohydrates per se.

While I acknowledge the study was small and relatively short-lived, I found it interesting that there was no difference in perceived hunger. As someone who responds quite strongly to blood sugar level peaks, the moderating my hunger was one of the key reasons I started looking at cutting back my carbohydrates. I’ve of late been trying to push the fat content of my diet up, but now I’m wondering if I should be trying to push protein instead.

 

Gary Taubes – Good Calories, Bad Calories

I am currently reading Gary Taubes’ Good Calories, Bad Calories. I’ve been vaguely familiar with the idea of low carb diets for a while – and tried Atkins which was effective to both lose weight and regulate my crazy appetite though I didn’t follow it for very long or adhere to much more than the second phase during that time.I did read the Atkins diet at the time but didn’t really take much of the science in and skimmed all the personal testimonies so got through it very quickly without retaining much.

Recently, I’ve been getting more interested in understanding why things work or are good for us, as well as wanting to clean up my life (and how to properly). I read the Paleo Solution by Rob Wolf as I’d come across the idea of a paleo diet as a healthy eating lifestyle and reviews I’d read indicated that this was a good balance between easy reading and science. This is really about the problems of food we haven’t evolved to eat – eg gluten and lectin in grains, but also the issues of carbohydrate vs fat and protein consumption on our health. I’ll be looking further into the more paleo side of this later but it did drive me to look further into getting a better understanding of the science behind restricting carbohydrate consumption aside from the (pretty damn conclusive) fact that hunter-gatherer man did not eat a diet high in carbohydrates. I’m still working my way through the book, which covers both the science and the history of the competing studies, but I’m lead to believe this is a very good summary (I’ve only quoted the final findings):

Summary of Good Calories, Bad Calories by Greg of Guts and Black Stuff

1. Dietary fat does not cause obesity, heart disease or other chronic diseases.

2. Refined carbohydrates, through insulin secretion, do.

3. Sugars, especially those including fructose, are particularly harmful.

4. Refined carbohydrates are the dietary cause of heart disease and diabetes. They are the most likely (but not only) dietary cases of cancer, Alzheimer’s disease, and other chronic diseases.

5. Obesity is not caused by overeating or sedentary behavior.

6. Calorie restriction does not cause long-term weight loss, it causes hunger.

7. Fattening and obesity are caused by a hormonal imbalance, which can be driven by diet (e.g. insulin secretion).

8. Insulin is the primary regulator of fat storage.

9. Carbohydrate intake drives insulin, and is therefore proportional to our body composition.

10. Carbohydrates also increase hunger and decrease energy.

Female Athletes – eat more protein, eat less carbs

I recently came across a study from 2006 looking at the dietary needs of women performing resistance exercises.  This study showed that women were less responsive to glycogen during exercise, less able to utilise carbohydrates for glycogen replenishment and required more protein then men post exercise. The advice from the study is that women should lower their carbohydrate consumption and increase protein and fat.

Nutritional aspects of women strength athletes

• Less use of glycogen in women during resistance exercises (also sprints – yay HIIT)

For example, a repeated maximal knee extension protocol resulted in significant glycogen depletion in type I and II muscle fibres in trained and untrained men, but this was not found in women.An attenuated reduction in glycogen in women after resistance exercise is consistent with similar observations after sprint exerciseand may result from lower glycolytic enzyme activity in women or a suppressive effect of estradiol.This gender difference in carbohydrate metabolism during resistance exercise may also be explained by the fact that women usually have a greater capacity for lipid breakdown and oxidation compared to men, such that glycogen is spared more in women than in men.

• Increased fat oxidisation post-exercise when doing resistance exercise rather than cardio. Carbohydrate demands post exercise are lower.

Immediately following resistance exercise in women, the respiratory exchange ratio (RER) significantly declines indicating an increase in fat oxidation during recovery.This significant decrease in RER post‐exercise has been noted by several investigators when resistance exercise was compared against sitting and against treadmill exercise with the same aerobic energy cost.  Elevations in fat oxidation post‐exercise spare exogenous carbohydrate for glycogen replenishment and underscore the importance of IMTG and dietary fat as an energy source.

• Advice on carbohydrate consumption:

One reason that high carbohydrate diets are not optimal for women strength athletes relates to the finding that women use significantly less glycogen during resistance exercise than menand synthesise less glycogen in response to a given amount of dietary carbohydrate.

carbohydrates with low glycaemic indices should be chosen to reduce the risk factors for cardiovascular disease, stroke, and diabetes as observed in women who consume higher glycaemic carbohydrates. Low glycaemic carbohydrates are rich in dietary fibre and contain important micronutrients, such as iron and B vitamins. These micronutrients are commonly found to be suboptimal in diets of women athletesbased on evaluations of self‐reported food intake and some biochemical indices of mineral and vitamin status.Fruits, vegetables, brown rice, enriched whole grain breads, whole grain prepared cereals, rolled oats, beans, legumes, and sweet potatoes are good examples of low glycaemic carbohydrate foods that strength training women should consume.

• Advice on protein consumption

Although studies are inconsistent with regards to gender differences in protein metabolism,there is some indication that leucine oxidation is greater in men, and women may oxidise less protein during exercise because they derive more of their exercise energy needs from fat.

An area of particular interest in protein nutrition is the concept of timing and the differences that may exist between genders. In contrast to men, women have an attenuated increase in muscle protein fractional synthetic rate when amino acids are provided after exercise, suggesting that women may need to consume more protein after resistance exercise in order to elicit the same anabolic environment.

• Addressing health concerns of a high protein diet (quoted at length – my highlights)

High protein diets have long been criticised on the basis of deleterious effects on bone due to their greater acid load that requires neutralisation by calcium salts.Women are at increased risk of osteoporosis as they age, so any potential adverse effects on bone health should be avoided. However, the justification to limit protein based on this criticism may not be warranted. Using dual stable calcium isotopes to quantify calcium kinetics in women, Kerstetter et al found that a high protein diet did not have any negative effects on net bone balance. Further, a protein supplement (42 g protein, 24 g carbohydrate, 2 g fat) given to young women and men throughout a 6 month strength and conditioning program, increased insulin growth factor‐1 and serum bone alkaline phosphatase (indicating increased bone formation) compared to a carbohydrate supplement of equal caloric value. Dietary unprocessed sources of protein contain both calcium and phosphorus and can contribute to increased dietary calcium and phosphorus intake. High protein intake does not appear to have adverse consequences for bone health in females, but rather, may be beneficial. Another criticism of high protein diets is that habitual consumption in excess of recommended intakes promotes chronic renal disease through increased glomerular pressure and hyperfiltration. On the contrary, the effects of high protein diets consumed by healthy humans were recently reviewed and it was concluded that there is insufficient proof to limit protein intake for the purpose of preserving renal health in healthy adults. The Institute of Medicine has also concluded that there is no clear evidence indicating that high protein diets have other deleterious effects including increased risk of cancer or cardiovascular disease. The final most common criticism against high protein diets in relation to strength athletes is that increasing protein intake beyond the recommended level is unlikely to result in additional increases in lean tissue because there is a limit to the rate at which protein tissue can be accrued. The argument against this statement is that even if there is a limit to gains in lean mass with high protein ingestion, increasing evidence shows that dietary substitution of carbohydrate with protein results in a variety of favourable health effects including enhanced weight loss, reduction in truncal adipose tissue, optimal maintenance of blood glucose, and improved lipid profile.

• Advice on fat consumption

women seem to rely less on glycogen for resistance exercise than men. Thus, high fat diets may be advantageous for women strength athletes to complement energy production derived from IMTG and circulating lipids while concurrently sparing muscle glycogen

Investigators have demonstrated that women endurance athletes in energy balance need to obtain at least 30% of their energy from dietary fat to ensure rapid replenishment of IMTG following exercise. If fat intake is sub‐optimal, there is continued IMTG depletion following exercise for up to 2 days, which may limit performance in subsequent exercise sessions.

Fat intake greater than 15% of energy from unprocessed sources may help to prevent the female athlete triad as its consumption will help attain energy balance, improve bone health, and avoid depressed sex hormone concentrations.