In 1970, two time Nobel prize winner Linus Pauling published a book called “Vitamin C and the common cold”. In it he argued that large supplemental doses of vitamin C could be used to decrease the length and severity of colds. This was the beginning of decades of controversy surrounding vitamin C (a.k.a. ascorbic acid) and its role in preventing respiratory infections, and resulted in Linus Pauling spending the last few decades of his life being derided as a quack by the medical establishment. But was he wrong?
In recent years, one of the most popular diet interventions has been fasting, in a variety of different forms. These have included intermittent fasting diets in which you’re supposed to fast for a few days per week, such as the 5:2 diet, or a few days per month. They’ve also included various forms of time restricted eating, such as the 16:8 diet, where you’re supposed to get all your calories within an eight hour window each day, and the more extreme warrior diet, in which you’re supposed to get all your calories in a four hour window. But there is still little clarity on how effective these modifications are in terms of weight loss. And up to this point, pretty much all the evidence in support of fasting comes from animal studies, which are notoriously unreliable.
“Only a minority of people in Sweden have antibodies, so they can’t have herd immunity!”
That is the most common argument I’ve been hearing for why Sweden can’t have achieved herd immunity. This is in spite of the fact that the rates of hospitalizations and deaths have dropped continuously since the peak in April, and are now stable at basement levels.
Considering how much misinformation is currently floating around in the area of health and medicine, I thought it might be useful to write an article about how to read and understand scientific studies, so that you can feel comfortable looking at first hand data yourselves and making your own minds up.
UPDATE 14th November 2020: In light of the recent increase in hospitalizations and deaths during October and November in Sweden, I no longer believe that Sweden reached a state of herd immunity during spring. The text below represents my thinking on the 19th of September, when I wrote the article, and doesn’t represent my current thinking. It is clear that a significant level of population immunity did build up during spring and summer, since the rise in hospitalizations has been much slower during the autumn than it was during the spring, and also seems to be stabilizing at a much lower level. However, the level of population immunity is clearly not as high as I previously thought. The reason I made this mistake is that the early evidence on covid suggested that it was not behaving in a seasonal manner. This caused me to underestimate the seasonal effect of summer to push down infections, which caused me to overestimate the level of population immunity that had built up during spring. It is now clear that covid is a highly seasonal virus.
In an earlier article we debunked the claim that exercise will help you lose weight. What about whether exercise will help you live longer? Now, don’t get me wrong, I am certainly not anti-exercise. There are lots of studies showing that exercise has many and varied health benefits, from improving muscle strength and balance, to decreasing the risk of fractures and delaying the onset of dementia. But will it help you live longer? And if it does, how much exercise should you be getting to maximize longevity? Are the famous ”10,000 steps a day” and ”half an hour a day” recommendations enough or should you be doing more than that?