Thursday, September 17, 2009

Tents

In the market for a new tent, and thought I'd record my research.

Requirements
  • Two person
  • Up to the challenge of Tasmanian (and NZ) weather: rain, mud, occasional snow (would be nice to use it for snow camping, too). Fine weather use isn't much of a concern - that's what tarps are for.
  • Would probably also get used as a car camping tent, although perhaps a dedicated cheap & heavy tent should be bought for that ..
  • Preferably two doors and vestibules (makes for comfortable use while travelling)
  • Closer to 2kg than 3kg
  • Good ventilation (decent amount of mesh in inner, ventilation in fly)
  • Bucket floor
  • Preferably integral pitch (i.e. fly first)

After a bit of looking around and asking knowledgeable gear junkies, I came up with the following shortlists. This thread on the Bushwalking Tasmania forums was particularly useful. And Bogong Equipment has got a brilliant overview of bushwalking tents.

I have both 3-season and 4-season shortlists. This is because I initially thought a solid 3-season tent would be sufficient. However, Tassie weather can get pretty bad, and it would be great to use it as a snow tent in the future, so I am starting to think a 4-season tent would be a better investment.

3-Season Shortlist

Macpac Macrolight
This tent is coming out in October, and will be on sale (30% off) for the first week. 2 entry/vestibule, 2 pole dome design. Looks to be a two-person, two-pole version of the Macpac Microlight. The Microlight is reputed to stand up very well to bad Tasmanian weather. Hard to say if the Macrolight would be the same. It has a wide-ish ridge that might hold snow. Will have to check out the real thing in a few weeks!
Fabric: 30D (3500mm) fly, Torrentwear Light (5000mm) floor, 9.0mm poles
Weight: 2.0kg (min) / 2.2kg (packed)
Area: 2.8m^2 (internal), 2 x 0.71m^2 (vestibule)
Price: $650 (RRP), $455 (sale)

Mont Moondance II
3 season, 2 entry/vestibule, 2 pole dome design with short top pole
Fabric: 40D
Weight: 1.86kg (min) / 1.98kg (packed)
Area: 2.66m^2 (internal)
Price: $470

Note: this is not the Mont Krypton, which has a built-in footprint, which has been known to collect water and act like a bath!

MSR Hubba Hubba HP
The HP is warmer than the original Hubba Hubba, but lighter. 3 season, 2 entry/vestibule, unusual wishbone design (although essentially a dome tent). I had a look at this in Paddy Pallins. It is cleverly designed, and quite spacious. However, the single pole design means it suffers from twisting problems in high wind. Also, the floor is *very* thin - you would want to use the footprint with it.
Fabric: 20D (1000mm) fly, 40D (10000mm) floor
Weight: 1.7kg (min) / 1.93kg (packed)
Area: 2.7m^2 (internal), 2 x 0.8m^2 (vestibule)
Price: US$400 (AU$460)

Wilderness Equipment Dart 2
Free-standing, 3-4 season, 2 person, 3 pole dome-style. I had a look at this in MDs. It is a great tent. The third pole makes the vestibules very big and useful. Internally, it is very long and spacious. A notable minus is that the 3-pole design creates a large flat area on top. This might be prone to pooling water, or loading up with snow. Also, it is quite heavy. The inner is mostly mesh, so could get a bit breezy in there.
Fabric: 30D (1500mm) fly, 75D (8000mm) floor
Weight: 2.62kg (min) / 2.89kg (packed)
Area: ?
Price: $580 (RRP), $406 (on sale from MDs)

Also available in a cheaper but heavier 75D version, and a "winter" version (same design, less mesh). These add an extra 250g, and cost $500 (RRP). I would call this a 3+ season tent.


4-Season Shortlist

Terra Nova Superlite Quasar
We used the Terra Nova Hyperspace in base camp on my expedition to Glacier Benito in Patagonia. They were heavy, but bombproof. A friend tells me the Superlite Quasar performs similarly well, but is much lighter. 4 season, 2 entry, 4 pole dome design.
Fabric: 4000mm (fly), 7000mm (floor), 8.55mm poles
Dimensions: 1.05m (h) x 1.36m (w) x 2.17m (l)
Weight: 2.2kg (min) / 2.5kg (packed)
Area: 2.88 m^2 (internal), 2 x 0.74 m^2 (vestibules)
Price: $990 (RRP), $690 (shipped from US)
Pretty impressive weight for a four-pole tent!

Macpac Minaret
A 2-pole, single-entry, 4-season tent. I had a look at this one in-store. It looks like a pretty good design. Roomy enough inside for two people to sit comfortably, but certainly not spacious. Funny shape means it's best suited to one tall-ish person and one short. Vestibule is not big but is functional. Needs to be guyed out well to be any good in the wind or snow.
Fabric: 30D (3500mm) fly, Torrentwear XP (10000mm) floor, 9.6mm poles
Dimensions: 1.00m (h) x 1.15m (w) x 2.00-2.50m (l)
Weight: 2.1kg (min) / 2.4kg (packed)
Area: 2.35m^2 (internal), 0.9m^2 (vestibule)
Price: $750 (RRP), $525 (sale)

Hilleberg Nallo 3
Hilleberg do some great tents. I remember walking with a guy around Torres del Paine who raved about his very nice 1 person one. The Nallo is only single entry, but there is a version (the Nallo GT) with super-big vestibule. 4 season, 2 pole sloping tunnel design. There is a Nallo 2 but from all accounts is sounds a bit small for two, so the Nallo 3 would probably be better.
Fabric: Kerlon 1200, 9mm poles
Weight: 2.1kg (min) / 2.4kg (packed)
Dimensions: 1.05m (h) x 1.60m (w) x 2.20m(l)
Area: 3.4m^2 (internal), 1.4m^2 (vestibule)
Price: US$595 (RRP) = AU$770 (with shipping)

Hilleberg Kaitum 2
Two entry tunnel tent, with 3 poles. Looks similar to Macpac Olympus.
Fabric: Kerlon 1200, 9mm poles
Weight: 2.5kg (min) / 2.8kg (packed)
Dimensions: 1.00m (h) x 1.40m (w) x 2.20m (l)
Area: 2.9m^2 (internal), 2 x 1.2m^2 (vestibule)
Price: US$715 (RRP) = AU$910 (with shipping)

Mountain Hardwear Spire 2.1
Four-season, double-entry, 2.5-pole dome design.
Fabric: 40D (1500mm) fly, 70D (3000mm) floor
Weight: 2.13kg (min) / 2.31kg (packed) + 310g for footprint
Area: 2.61m^2 (internal), 2 x 1.0m^2 (vestibule)
Price: US$425 (RRP), ~AU$580 (with shipping), US$36 for footprint

Mountain Hardware also have the Skyledge 2.1, a similarly-design 3-season tent.

Mont Bell Stellar Ridge
4-season, double-door/vestibule 2-pole dome design. Doesn't look solid enough to be a mountain tent ... looks a bit like a Macpac Apollo.
Fabric: "Ballistic" lightweight materials: 1500mm fly, 2000mm floor, 10000mm footprint
Weight: 1.81kg (min) / 2.06kg (packed) + 295g footprint
Area: 2.7m^2 (internal), 2 x 0.52m^2 (vestibule)
Price: $650 + $50 (footprint)

Mont Bell also has the Chronos Dome which is a heavier and cheaper 3-season tent of similar design.

Exped Sirius Extreme II
4-season, single-door/vestibule tunnel tent. Looks pretty good. Better than WE Second Arrow. Similar to Hilleberg Nammatj 2 but cheaper?
Fabric: 10000mm floor
Dimensions: 1.00m (h) x 1.30m (w) x 2.25m (l)
Weight: 2.65kg (min) / 3.1kg (packed)
Area: 2.92m^2 (internal), 1.43m^2 (vestibule)
Price: US$360 (~AU$500), or $530


Honourable Mentions
There are a few other tents that I considered, but didn't make the cut for whatever reason.

Hilleberg Nammatj 2
Similar to the Nallo, but doesn't slope down towards the end. 4 season, 2 pole tunnel design.
Fabric: ?
Weight: 2.4kg (min) / 2.8kg (packed)
Area: 2.8m^2 (internal), 1.2m^2 (vestibule)
Price: US$575 (RRP), US$675 (for GT)

Wilderness Equipment Second Arrow
5 season, 2 person, tapered tunnel design (single entry/vestibule). Looks good in print, but in reality this tent is very small. It has a very low roof which makes the inside feel quite cramped. It is also quite short - I only just fit in. The single vestibule is not very big, but could be opened out in goodweather. Probably the First Arrow is a better option as a snow tent.
Fabric: 30D (1500mm) fly, 75D (8000mm) floor
Dimensions: ?m (h) x 1.30m (w) x 2.03m(l)
Weight: 2.28kg (min) / 2.57kg (packed)
Area: ?
Price: $600 (RRP), $420 (on sale from MDs)

Also available in a cheaper but heavier 75D version.

Mountain Designs Positron
Single entry, two-pole dome design.
Fabric: 40D siliconised fly
Weight: 1.74kg (min)
Area: 2.7m^2 (internal)
Price: $540 (RRP), $380 (sale)

One Planet Gunyah 2v
This thing is super-light! Probably too light for serious rain, but worth considering for the mainland ... Single-pole dome design, two entries, but only one vestibule.
Fabric: 15D fly, 20D floor
Weight: 1.35kg (packed), 1.66kg (with footprint)
Area: ?
Price: ~$540


Exped Vela II
3-season, two-door, two-vestibule tunnel tent.
Fabric: 10000mm floor
Weight: 2.65kg (min) / 3.05kg (packed)
Area: 3.2m^2 (internal), 2 x 1.25m^2 (vestibule)
Price: $600

Tarptent Scarp 2
Using just one pole, a light 3-season tent. Add another two poles for 4-season use. Don't like the look of the way the extra poles are added. Probably not that great in the wind.
Fabric:
Weight: 1.53kg (3-season), 2.01kg (4-season)
Area: 2.2m^2 (internal), 2 x 0.58m^2 (vestibule)
Price: US$325

Also want to know about some Salewa tents: Sierra Ultra, Sparrow II, Bergen II $230, Sierra Leone. But no info online!


I am waiting on more info on the Macpac Macrolight. If that looks good, then I think I will go for that. Have been very happy with Frightfully Delightful's Macpac Apollo, although it was a tad on the heavy side.

Friday, August 7, 2009

Amygdala re-training

I have recently started a CFS treatment programme that is based on a hypothesis that CFS is of neurological origin. Gupta Amygdala Retraining has been developed by a guy from London called Ashok Gupta. He is only young, and is not a medical doctor. He got CFS about 10 years ago. In the process of researching the condition, he struck on something that worked and got himself better. He then went on to open a clinic and has successfully treated a number of patients. His treatment programme is now available to buy as a set of DVDs.

When I first came across Gupta, I was fairly suspicious, because there are always cure merchants out there. But I encountered a few people who were trying it, and there seemed to be a fairly positive vibe coming from people in forums. He was also at the most recent International Association for CFS/ME conference in Reno, where he presented a poster, and has been seeking support to do a more comprehensive trial of his treatment. So I think he is kosher, and I have bought his DVD treatment programme.

He has done a clinical study of 33 patients. After one year, 92% improved, and 67% made a full (or very nearly full) recovery. Those are pretty encouraging numbers!

So what is Gupta's hypothesis? At the root of it is a part of the brain called the amygdala. As he explains it, the amygdala is responsible for generating emotional responses due to sensory stimuli. An example might be if you are in the bush and think you see a snake. The sensory input from your eyes enters the amygdala from the thalamus. The amygdala recognises the stimuli as looking like a snake. It then activates the sympathetic nervous system (i.e the stress response) via the hypothalamus, and makes you feel scared and anxious. All this happens before your conscious mind has had a chance to even form the thought "snake!"

The amygdala is capable of learning. So if there is indeed a snake, then your conscious recognition of that fact reinforces the response of the amygdala. If there wasn't a snake, then your amygdala would learn to not overreact to sticks on the ground.

How does this relate to CFS? Gupta proposes that the amygdala is highly sensitised in CFS sufferers. This results in a nasty vicious cycle:
  • Sensory stimuli relating to CFS symptons (tiredness, pain, etc.) arrive at the amygdala.
  • The amygdala, because it is over-sensitised, recognises these stimuli as bad.
  • It kicks off the stress response, which, because of this cycle, is chronic.
  • It also generates fear/anxiety in the concious mind.
  • The conscious mind recognises the symptoms, and agrees with the amygdala: "Yeah, that sucks, I really am tired!"
  • The amygdala learns that it has done the right thing, and becomes even more sensitised to the symptoms.
  • The chronic stress response actually is the cause of the CFS symptoms, and so we are back at the start of the cycle, and it continues onwards.
So it's all in the head? Well, not quite. The symptoms are real. But they continue because of the over-sensitised amygdala. Additionally, this is not a conscious process. Rather it is sub-conscious. So it is not a psychological problem, but rather a neurological one.

How does someone get stuck in this feedback loop to start with? Gupta contends that it is a combination of stress and infection. Someone might be in a particularly stressful period of their lives. They get an infection or virus. They get over the initial symptoms in a week or two, but then they never seem to quite get completely better. They have post-viral fatigue. As this drags on, they become increasingly aware of their symptoms, and angry and frustrated by them. This, then, trains the amygdala to treat the symptoms as a threat, and to trigger the stress response. And so the cycle begins.

This hypothesis has been published in the journal Medical Hypotheses, and is available online. Gupta has also made available some of his DVD sessions. Those where he explains the hypothesis begin here. He gives an overview of the treatment programme beginning here. And there are some testimonials starting here (the one with Rebecca is the best). Note that all up he has put about 3 hours worth of video up on youtube. On the plus side, he is really quite good at presenting it.

How does Gupta treat this? Well, I would be breaking his intellectual property to tell you, but it boils down to this. The only part in the cycle we can control is the part where the conscious mind reaffirms the actions of the amygdala. The key is to break the cycle there, and then gradually the amygdala will desensitise, the chronic stress response will diminish, and the body return to normal.

As I watched his DVDs, everything he said made sense, and I could relate to intimately. It really struck a chord with me, and I could look into the past and see how events and my behaviour had triggered various episodes. But more than anything, he knew exactly what was going on in my head, and why that was keeping me sick.

I've been applying Gupta's technique for nearly two weeks now. Is it helping? I think, yes. The last two weeks have been my best since about November. I have been more able, more energetic and more enthusiastic about life. Will it last? Only time will tell, but I feel positive that it will. I feel like I have the tools to deal with any dips, and the knowledge to recognise undesirable behaviour.

Is it hard to do? Yes and no. Persistence and awareness would be better descriptions of what is required. When I first understood the full consequences of the technique, and what it would demand of me, I had a "Holy Shit!" moment. He was asking me to completely turn around the way my brain had been operating! But after a few days of absorbing the concept, I found that my thinking had already started to adapt, and that I was naturally shying away from my old unhealthy thinking. It's like this understanding he has given me has flicked a switch in my head, and my brain has seen the light and is getting to work in this new direction.

Having said that, it's possible that I'm not really doing it properly, and that I need to be more diligent to get the long-term improvements.

One unanswered question I have, is that if the symptoms are due to a chronic stress response, shouldn't that be detectable in the levels of hormones etc. in the blood?

I should outline the other factors that may have led to my recent improvements in health. I was already on an up before starting Gupta, but I am quite confident that Gupta has enabled me to at least maintain that improvement, if not better it. Other things that have changed recently is that I have shifted towards a low-carb, paleo-diet, and that I am taking a bunch of supplements. I think they are both important contributing factors. In combination, I am hopeful that they will be enough to get me better again.

Fingers crossed!

Sunday, August 2, 2009

Eco-tarian meat eating

I've started eating more meat lately, and have been juggling the environment consequences of that.

To begin with, I bought some sausages from the local butcher. I did this because I can walk there and it's convenient. By contrast, to get kangaroo sausages, I need to drive to the markets. So, I wondered, is driving 14km to get a dozen roo sausages worse than walking to get a dozen beef sausages?

According to the Garnaut Report, emissions for production of meat are as follows (expressed in kg CO2-e/kg meat):
  • Beef: 24.0
  • Lamb: 16.8
  • Pork: 4.1
  • Poultry: 0.8
  • Kangaroo: let's assume 0.
Let's say a dozen sausages weighs a kilo. Then the beef sausages emit 24kg of CO2. To drive 14km, even in my old Magna, would produce only 4.1kg of CO2. That means I could drive about 80km to get my roo meat, and come out even. Wow!

At Coles the other day I noticed that they now have a "game meat" section. Not only was there kangaroo, but also wild goat sausages, vension steaks, and a bunch of other things. All of these animals are hunted in the wild, and are feral pest species. This is fantastic! So by eating this meat, I can help reduce the number of ferals animals causing all sorts of environmental degradation, and reduce greenhouse emissions. With kangaroos, I only avoid emissions. Who'd have thought you could do better than roo?

My housemate tells me that they are hunting feral camels for meat in NT and WA. Camels produce a lot of methane, and there is something like a million of them out there. The camel hunters are hoping to get emission credits for the emissions the camels would have produced if allowed to live!

Monday, July 20, 2009

IQ over education?

This is a nice controversial piece. Bruce Charlton argues that IQ and psychometric tests could be used to a much greater degree in the education system. This would cut out a lot of inefficiencies and shorten the amount of time we spent studying.

He argues that IQ is 80% hereditary, and that personality is 50%. So the basic make up of a person's intellect and inclinations is essentially a given from birth. A lot of what the education system does is determine which students are the most conscientious, and then give them a piece of paper so that employers know who to employ. This could be done much more efficiently by simply measuring IQ and doing psychometric tests in order to work out who would be the best fit for an employer. (Apparently the US Army already does this internally.)

Further, he argues that the way in which we think is essentially hard-wired - if someone isn't good at maths, then in the long-term, they are never going to learn to be much good at it. Much better, he says, to work out what people are good at, and then teach them that sort of stuff. He proposes that everyone learn a basic common curriculum, including literacy and numeracy. When they reach 16, they are sent into the world with their IQ and personality having being measured. These would be used to determine what career they should take. Further education would be completely content-focussed, rather than teaching how to think.

Definitely worth a read! Fat chance of it every happening, though.

Good Calories, Bad Calories

"Good Calories, Bad Calories by Gary Taubes is held up to be something of a bible by those on the low-carb diet bandwagon. From what I've read about it, it:
  • attempts to destroy the conventional wisdom that low-fat diets are good for you
  • explains how not all calories are created equally, due to the different ways carbs, fats and protein get metabolised
  • explains how carbohydrates cause havoc with insulin and blood sugar, and how this leads to appetite problems
  • explains how carbs cause heart disease
How solid is the science? The book seems to be painstakingly detailed - unusually so for a mainstream diet book. And it has certainly gotten a mixed response, with many lay-folk latching on to it with enthusiasm, and those in the research community pooh-poohing it. I won't link to all the various critiques and discussions that are out there, but a good starting point is here. It seems to at least mark a turning point in our understanding of nutrition.

Taubes' position is that obesity is caused by consumption of carbs, whereas the conventional view is that is is an energy balance problem. From what I've read, it sounds like no diet has been shown to be particularly effective in the long term, and that any diet can provide short-term weight loss.

But I'm not particularly interested in weight loss. It is the other health effects of carbohydrates that interest me more. There appears to be less argument over the way carbs cause heart disease - but perhaps I wasn't looking hard enough. Carbs are also a cause of inflammation, which some hold to be a source of many diseases. But this seems to be more hypothetical.

I'm going to have a crack at this low-carb malarky and see how my body responds. The only experiment that counts is the self-experiment!

Sunday, July 19, 2009

Digestibles

Here is a handy little page that gives some simple pointers on what sort of blood sugar levels to aim for. In short, your fasting level should be below 5.5 mmol/L, one hour after eating 7.8 mmol/L, and two hours after eating 6.6 mmol/L.

And here is a great post looking at how ancient cultures used to eat grains and legumes. They soaked, sprouted and fermented them, in order to remove the natural toxins and anti-nutrients such as phytins, lectins and tannins.

Here is a terrifying account of an extreme case of ME/CFS. Extraordinarily, he found a doctor who understood what was going on and saved him.

Dr Art Ayers talks
about a link between Celiac Disease and Hashimoto's Thyroiditis. This is interesting to me because my mum has Hashimoto's, and has had issues with wheat in the past.

Saturday, July 11, 2009

Supplements

I ordered a bunch of supplements from the US. As far as I can determine, the industry is more regulated here in Australia than in the US, so the trade off is lower prices, but less assurances that I'm getting what I expect.

Basically I am trying to ensure a good dietary basis for my health, as well as target some particular CFS-related areas.

Magnesium
As I've mentioned previously, magnesium is a common deficiency in CFS sufferers, and indeed, more generally. I'm aiming for up to 750mg/day. An initial analysis of my diet indicates that I get about 400mg/day from my diet, so I'll take 300mg/day via supplement.

I've got a magnesium chelate, which has calcium in it as well. 83 days worth, at $0.15/day.


Vitamin D
I've touched on Vitamin D before as well. It turns out that at 88nmol/L my Vitamin D levels are just fine. But since I've already got the supplements, I will take 2000IU per day until the end of winter or so. 150 days worth, at $0.08/day.

Omega-3
It's very important to get your intake of Omega-3 and Omega-6 fats in balance (I intend to write a post on this in the near future). I'll take 3600mg/day of Omega-3 EPA & DHA from fish oil, which gets me about a 1:4 ratio with my dietary Omega-6. 40 days worth, at $0.85/day.

Probiotics
Yay for gut flora! This is probably worth a post too - they've done some amazing experiments with gut flora. I've got a probiotic with 35 billion units of 15 different strains. Maybe when I'm done with those, I will try more specific strains that have been implicated in the recent H2S CFS discovery. 60 days worth, at $0.71/day.

Iodine
I bought this on a bit of a whim. I came across a post that got me thinking, and realised that I have virtually no source of iodine in my diet. And at $4 for a little bottle, it's not a big expense! 240 days worth, at $0.02/day.

All up, it's costing me $1.80/day. Not cheap, but worth experimenting with for a few months. Combined with a shift to a paleo diet, and the Gupta Programme, perhaps I will see some improvements.

Wednesday, July 8, 2009

Digestibles

I found an article which summarises the work of an early researcher into paleolithic diets. It gives a short but sweet overview and is certainly worth a read.

And here is an awesome extensive rant against the food pyramid and carbohydrates.

I had a feeling soy was bad. This site gives a good rundown of the concerns. Not too many scientific references, though.

Hmmm, those last two are not the most reliable sources in the world. Read with scepticism!

Celiac Disease more common now than 50 years ago?

Celiac Disease seems to be increasingly prevalent, and it is now relatively easy to find cafes and restaurants to cater for a gluten-free diet. So is the rise in Celiac Disease due to increased awareness of the condition, or has is actually become more common?

The Mayo Clinic in the US has done a study with frozen blood samples from Air Force recruits in the 1950s. They discovered that Celiac Disease is about 4 times more common now than it was then. In addition, they found that those with undiagnosed Celiac Disease were four times more likely to die than those without. You can read the abstract of the study here.

A big caveat on this: they didn't compare the 1950s Air Force samples with contemporary Air Force samples. They compared them with the general public (although matched for age and sex). I would imagine that Air Force recruits would be in better health than the general populace, and so would be less likely to have Celiac Disease. Sigh, why is it so hard for studies to be done properly?
Link

Saturday, July 4, 2009

Vitamin D

It appears that Vitamin D is a surprisingly important vitamin. I'd always thought you just needed a little bit of sun exposure and you'd get enough. But maybe not. Deficiency seems to be surprisingly common. Evolutionarily it makes a certain amount of sense, as we evolved being outside all day wearing not very much. Now we huddle in offices and, particularly in winter, barely get any direct sunlight.

I first came across this idea thanks to a post by Dennis Mangan. Not long after, someone with CFS emailed OzME (an Australian ME/CFS email list) reporting that their doctor had tested their Vitamin D levels and that they were low. They recommended everybody get theirs checked, in case they were deficient, because it is involved in all sorts of body processes, especially immunity. Seems like the sort of thing that you don't want holding your immune system back, when it's got a hard job to do.

A good resource about all of this is the Vitamin D Council. They have some good articles on checking for deficiency, and how Vitamin D could be used to treat swine flu. There is lots more stuff on how Vitamin D is involved in depression, cancer and autism. Dennis Mangan has a bunch of interesting posts on the issue which give a good overview.

And here is an interesting article on how much money could be saved if everyone in Northern Europe got enough Vitamin D (quick answer: about 18% of total health expenditure!).

I saw my doctor the other day and she was quite happy to test my Vitamin D levels. She said she's doing more and more of it, and that a surprising number of young females are deficient. She said it should be up around 80ng/mL, but didn't suggest as big doses as the Vitamin D Council.

So in a few days I'll know if that is a factor in my CFS puzzle!

What I haven't worked out is if animals synthesise Vitamin D from sunlight, and if so, how do they manage it when they are covered in fur?

Monday, June 29, 2009

Fibre: not so great?

Dr. Michael R. Eades rips into fibre, suggesting that the need for regular bowel movements isn't what it's cracked up to be. If he's right (he doesn't really destroy the idea, just suggest that the mechanism behind it seems strange), then it would support the Paleo Diet idea that grains (which are high in fibre) are bad.

Hmmm, might stop adding the psyllium husk to my muesli ...

Saturday, June 27, 2009

Paleo Diet

I've been doing lots of reading on diet lately. I came to the Paleo Diet via two paths: my boss has successfully lost a good twenty kilos by adhering to it, and it's a logical extension of the grain-free diet I've been testing out.

What I like about the Paleo Diet is that it is not based on our rather hazy understanding of the biochemistry of the human body, but on our understanding of evolution. It's simple: for the vast bulk of the history of the human race (say 1 million years), we lived as hunter-gatherers. It is only in the last 10,000 years (if that) that we've had agriculture and have eaten the foods which that has provided. The Paleo Diet is based on the premise that our bodies have evolved to eat a hunter-gatherer diet, but not an agricultural diet. One can further surmise that the many "diseases of civilisation" may be rooted in the current dependence on a diet to which our bodies are not accustomed.

So, what did a hunter-gatherer diet look like? Apparently, they got about 45-65% (by energy) of their food from meat (indeed, the Inuit's complete diet consisted of meat). That is: hunted game, eggs, fish and insects (witchetty grubs and bogong moths!). The rest was plant food such as leaves and roots, and any fruit and nuts that were in season. Obviously the exact food varied from region to region, and from season to season. What was notably absent was food high in carbohydrates, such as grains, legumes and potatoes.

By comparison, the modern diet is overly dependent on high-carb foods and sugar. Obesity and diabetes are an obvious result of that. I'm not sure of the mechanism, but high-carb, low-fat diets seem be bad for heart disease.

Mark Sisson provides an overview of how much carbohydrate we should eat. The typical modern diet consists of about 150-300g of carbohydrate per day, with the upper end leading to rapid weight gain and disease risk. He suggests aiming for 100-150g of carbohydrate per day on a Paleo Diet. Going for less makes it easy to lose weight, particularly under 50g/day (where your metabolism starts doing some interesting things!).

So how much protein? Mark Sisson suggests you aim for a minimum 0.5g/lb of lean body mass (i.e. your weight, minus the fat), and 0.7/g to 0.8g/lb if you're are moderately active. So that's 1.1-1.7 g/kg of lean body mass. I weigh 68kg, and would guess my lean body mass was about 60kg, so I would need to aim for 65-100g of protein. Thanks to CFS, I'm not very active at all so the lower figure will do. Conventional wisdom says to aim for 0.8g/kg of body mass, so the Paleo Diet is hitting the protein a fair bit harder.

The energy balance comes from fat - and it needn't be polyunsaturated fat. Saturated fat is fine, and omega-3 fats are best. I'll write more on fats later.

Next post, I'll do breakdown my typical daily diet and work out what I need to change to go Paleo.

Monday, June 22, 2009

Magnesium

I remember in high school chemistry when we used to burn little strips of magnesium. A star of bright light ensued! But apparently magnesium is an important nutritional mineral. It is involved in quite a lot of important metabolic reactions.

Apparently, most people are magnesium deficient, thanks to the modern-day diet (most Americans get about half the RDI). It is also often used to treat CFS, with some success.

Mangan has an interesting post on magnesium and depression. Mg deficiency leads to increased inflammation, which can be an underlying cause for a great number of diseases. Oh, and here is an absurdly detailed page on magnesium and depression.

I found this page gives a useful overview on how best to supplement. In short:
  • Use a magnesium chelate, as these are best absorbed.
  • Don't take it all in one go - spread it out during the day, as there is a limit to how much you can absorb at a time.
  • RDI is 400mg/day, but this is a bare minimum. Aim for 5-10mg/day of ideal body weight. So for me, that would be 350-700mg/day, and I would go for the higher number because of my CFS (which may implicate Mg deficiency).
When I finish this grain-free experiment, I'll give magnesium a go. Probably about 200mg three times a day to start with.