In the world of health foods, natural diets, and alternative nutrition, there are scads of scientific studies cited that demonstrate the "possible" value of this or that nutrient, supplement, or other non-mainstream dietary item. All these things "may" have "possible" benefit for some group of users.
This is the way the public sees scientific studies of health and fitness, and Adams is absolutely right in calling science on it. Even given that science is always conditional, always likely to contradict earlier "truth," there is far too much reportage that just veers from extreme to extreme in the realm of nutrition. There are far too many studies that aren't carefully designed, or are studying to a predisposed result, or are just shams for some corporate agenda. The good ones are likely to be mis-reported by one or more popularisers, or have significant factors ignored in the media, or in some other way be distorted when made public. Even when the science is excellent, the reportage is likely to be horrendous.
The bottom line for me, at least, is that I'll eat what I want, do the exercise that I want, and try to avoid the things that seem too nutty to be valid. That's not very scientific, I guess, but it beats being led around by the nose by competing studies and experts.