The tragedy is that after generations of blind, almost religious belief in flawed science those raised on a diet of synthetic fats, sugar, and refined flour are suffering obesity and diabetes like never before.
Half a century ago we were worried sick about global cooling. Sure, we know more now than we did then. But that is not a valid response: in any decade we know more than in decades before that.
Most of the measures for global warming mitigation either directly cause massive economic costs (large taxes, etc, etc, which all end up preventing the same sort of progression that is allowing us to bootstrap!), are short-sighted (Carbon credits leading to old-growth forests being cut down), directly cause deaths (banning of CFCs leading to deaths due to the alternative puffer propellants not working as well), etc. Or end up as a combination of both.
For that matter: there are viking farms in what has been permafrost for the last ~500 years. We (assumption here) were not industrialized at the time. So: why was it not permafrost? And for that matter, considering the greenland ice sheet was not the size it is today at that time (again: assumption based on the fact that, you know, it wasn't permafrost at the time), why was the sea level not higher to the extent that people are predicting?
And the question is: for what gain? (For example: a large chunk of the Canadian shield, while good farmland, is primarily growing season limited. It seems plausible that higher temperatures could increase their yields. So: has anyone crunched the numbers? Plants grow better in higher CO2 concentrations. Etc.) And what alternative measures could be taken? (For example: dropping a nuke to trigger a volcano would lower global temperatures. We know this.)
It's my children's world that I'd like to build up here, and my children's children. I'd like to make rather sure that we know what we're doing. There is no rash decision quite like one affecting the entire globe for centuries.
The situations are different here. It's not like in 50 years we'll discover that "hey, wait a minute - inhaling coal fumes is actually good for us!" - which is what you're trying to imply with your comment.
I get where you're coming from, but I do think you're being a touch disingenuous with questions like 'has anyone crunched the numbers?' Of course people have considered that higher CO2 concentrations could come with benefits as well as costs. Here's an optimistic crunching of the numbers, finding a $3.5 trillion benefit over the last 50 years, although I thinkt he methodology is severely flawed: http://www.co2science.org/education/reports/co2benefits/Mone...
And here are some explanations for why the relationship between CO2 availability and agricultural productivity is non-linear: https://www.skepticalscience.com/co2-plant-food.htm
I have to say that if you are as concerned about your descendants' future as you say, then I think it's time you did more of your own homework.
As for CFCs, the main problem I've been aware of resulting from the ban that might have resulted in deaths was due to the increased cost of asthma medication. Do you have any data to quanity how many deaths this has supposedly caused? Would you say that this is more or less than the lives that would otherwise be lost to skin cancer?
CFCs were banned because they were destroying the ozone layer, and the ozone layer protects us from excessive UV-radiation (which causes skin cancer). This was not related to global warming.
Why does the inevitable increase in accumulated knowledge imply that it doesn't make sense to base decisions on the current state of that knowledge? It sounds like you haven't thought this argument through.
Repeated, rapid fluctuations in the scientific opinion or lack of broad consensus would be warning signs, but neither of those are present.
> So: has anyone crunched the numbers?
Yes! That's what scientists do for a living. They publish detailed records of their data-->conclusion inference process, high-level scientific summaries of those individual results (reviews), and higher-level nonscientific summaries of their cause/impact/mitigation conclusions (IPCC reports). Thousands of them sign statements saying that their individual contributions weren't misrepresented in the high level reports, and then individual members of the community go forth and represent that consensus to the media and to politicians.
And then people like you notice that their soundbytes don't constitute a formal inference process and use this fact to argue that the scientists don't know what they're talking about. Of course, you're too damn lazy to dig through their painstakingly constructed pyramid of results and see for yourself, so you have to keep your feet firmly planted in "my ignorance is as good as your knowledge" territory to keep up the argument. This should tell you something.
> Plants grow better in higher CO2 concentrations.
Do you really think this escaped the notice of thousands of specialists with millenia of accumulated experience?
Answer: it didn't. Here's the latest report I've seen addressing this issue. There have been plenty of other reports answering permutations of this question, but they weren't published last week in Science, so I'd have to use google scholar to find them.
http://www.sciencemag.org/content/344/6183/508.abstract
> I'd like to make rather sure that we know what we're doing.
"Doing nothing" is doing something -- something that the only people in a position to make credible predictions regarding the effects of what we're doing are awfully worried about.
> dropping a nuke to trigger a volcano would lower global temperatures. We know this.
You seem far more confident in your ability to predict the climactic effects of a nuke in a volcano than in the scientific community's ability to predict what happens when we dump an insane amount of CO2 into the atmosphere. Why?
A child could tell you why the volcano would be a bad idea. I'm quite certain you've not given this nearly as much honest thought as you think you have.
The attitude of "settled science" is what kills science.
The type of people who end up (or even aim for) in government regulatory bodies, are usually not the cream of the cream of scientists.
Nope. "We" have realised that there's money to be made in selling contrarian diet books that tell people what they want to hear.
Meanwhile in Europe they keep eating whatever they always ate (in moderation), not drinking soda, keep drinking (more moderately hopefully), and don't need a motorized cart to shop at a supermarket.
Even though it's hard to believe, I wouldn't doubt someone found out traditional Belgium fries (yes, in lard, yes, with a good amount of mayo on top) may end up being healthier than a lot of "low fat" crap in a supermarket
I think the point of all this new research is that you can't take out fat and expect your diet to be healthy--the real story is much more complex. Most educated people would realize eating lowfat cookies still isn't a good habit to have, but society seems to think it's ok.
The anti-sugar hysteria a la Lustig is the other shoe to drop. The fear mongering is a bunch of baloney when you look into it.
If you live in USA you probably have too much sugar in your diet if you're not taking any steps to reduce it. When my wife(and her mom) first came to USA from Nigeria, they both complained that everything tasted like sugar. Even dinner-type meals that are suppose to be savory. I also have a relative who doesn't need their medication to control their blood-sugar when they're in Nigeria instead of America.
Also, on my own quest[1] to be healthy and reduce my weight everything ultimately came down to reducing carbs and sugar in my diet. Lost nearly 40 lbs. People always say I look much younger than my age and I have trouble getting into Nightclubs sometimes since I don't look like my driver-license picture anymore.
1. http://smtddr.hatenablog.com/entry/2011/06/19/Wii_Fit_Plus%3...
It's just a throwaway joke in the story but I'm convinced it would absolutely work in real life.
Seriously, this is a worry. When I was younger I thought the Internet would make the scientific method go mainstream, with Usenet and later the web functioning as a sort of intellectual meritocracy.
Note to idealists: expect less and you won't be disappointed.
A meta-analysis of 8 randomised controlled trials with 13 thousand subjects showed that a 5% total energy substitution from saturated to polyunsaturated fats reduced risk of coronary heart disease by 10%.[1]
The point about substituting hydrogenated fats is good; but it's hardly an argument for switching back to saturated fat. It's an argument in favour of not eating unhealthy food in the first place.
But that's not how you sell books, is it?
[1] http://well.blogs.nytimes.com/2014/03/17/study-questions-fat...
Moreover, it was subject to numerous corrections due to sloppy work by the authors:
http://news.sciencemag.org/health/2014/03/scientists-fix-err...
What about only reducing saturated fats by 5% (replacing it with carbs, or something else?) and maintaining PUFA levels?
What about adding the PUFAs, maintaining SFAs and reducing caloric intake somewhere else?
Consumption of PUFAs have a known effect on cardiac health, so the result of this work is 1) not surprising 2) saying nothing about SFAs (what about diets with different levels of SFAs and no difference in PUFAs?)
After many discussions with many people about what is or is not healthy and a lot of reading, I've come to believe two things:
1. We (scientific and non-scientific community) have no clue what is or is not healthy, and it probably varies from person to person, and
2. The human body is really good at giving indicators as to whether or not it is healthy. With a bit of experimentation (food/exercise) and attention to physical and mental well-being it's not hard to assess one's health.
The difference for me after going Paleo was noticeable after about two weeks -- improved memory, energy, happiness, sleep, lots of other stuff. I've heard similar stories from others that have become vegan, vegetarian, discovered high-FODMAP insensitivity, etc.
Shameless self-promotion: I built http://www.fitsmeapp.com to help find food (currently just recipes) based on arbitrary user-defined "diets". Feedback is always appreciated.
Any meat, any vegetables, decent amount of fruit, any kind of potatoes, butter, some nuts. It's a bit of a deviation from the by-the-book version (whatever that actually is -- it varies depending on who you talk to) because of potatoes and butter.
People will make "Paleo Cookies" and other baked goods usually with a combination of nut-flours, potato starch/flour and honey for sweetener (among other things). They tend to look ugly and taste pretty bad. Not to mention contain lots of sugar (which, even if it's honey, ends up defeating the purpose proportional to how cookie-like you want it to taste). I have made things like that though -- cookie cravings happen.
If you mean in Fitsme:
We have something fairly close to what's probably mentioned by Crossfit -- but it's 100% configurable, so it can have whatever you want it to.
Study Questions Fat Heart Disease Link http://well.blogs.nytimes.com/2014/03/17/study-questions-fat...
A Lifelong Fight Against Trans Fats http://www.nytimes.com/2013/12/17/health/a-lifelong-fight-ag...
The Oiling of America https://www.youtube.com/watch?v=fvKdYUCUca8
Even I admit that my chasing of labels such as Non-GMO and USDA Organic could also be a big marketing scam and they could very well be selling me the same pesticide-soaked, GMO-glued-together, sweetener-laced, antibiotic+steroids pumped food that everyone else is buying while charging me a 40% markup for a lie. But since I'm confident we're all just rolling dice here, I choose to gamble on chasing food that's supposedly very similar to what my family has been getting it for generations in Nigeria with no particularly notable health issues except 2 instances of diabetes. One of them came to America, started eating all the common fast foods, drinking, smoking, etc for over a decade. The other is related to depression and change of eating habits while still in Nigeria.
If I'm wrong... I'm wrong. But I hope this lets people know that our current science(and social/economical incentives around it) is not good enough to use as a debate-closer of health & fitness discussions. There are contradictions[2][3] out there. I suspect that at the end of the day, what's good for one person can be poison for another and all our attempts at generalizing health & fitness guidelines for everyone will ultimate end in failure. We'll all have to go into the hospital, get a DNA sample and get customized health & fitness advice - and that's assuming we can remove the economic incentives for hospitals/doctors to just tell us whatever it takes to sell some expensive "solution".
1. https://news.ycombinator.com/item?id=7671699
2. "Many of the bacteria are species that the researchers had never seen before. And even familiar microbes were present in unusual levels in the Hadza belly. “The Hadza not only lack the ‘healthy bacteria,’ and they don’t suffer from the diseases we suffer from, but they also have high levels of bacteria that are associated with disease,” Crittenden said." ---- http://www.wired.com/2014/04/hadza-hunter-gatherer-gut-micro...
3. " Unlike their Western counterparts, the Tarahumara don't replenish their bodies with electrolyte-rich sports drinks. They don't rebuild between workouts with protein bars; in fact, they barely eat any protein at all, living on little more than ground corn spiced up by their favourite delicacy, barbecued mouse. ---- http://www.dailymail.co.uk/home/moslive/article-1170253/The-...
The very cornerstone of dietary advice for generations..."
...is being challenged because:
Critics have pointed out that Dr. Keys violated several basic scientific norms in his study.
It's a cautionary tale worth telling no matter the discipline. Studies are often accepted without much challenge because we assume that rigorous controls were in place. But the adage of "Garbage in, garbage out" remains a fundamental truth. I think that is what is relevant and interesting to HN readers.
Even in the context of traditional diets there are good ones and bad ones.
Do you want to look like this guy: http://www.kimmacquarrie.com/wp-content/uploads/2012/07/Mash...
Or this guy: http://1.bp.blogspot.com/-rTRD-USWhSk/UTIwrhmGFcI/AAAAAAAAAT...
They both eat traditional diets, clearly with very different physiological outcomes.