>When you consider the fact that Brazilian diets are commonly high in fat – meat is often eaten for all three meals of the day – it’s no surprise that hypertension, diabetes, cancer, obesity and cardiovascular disease are on the rise.

I'm sad to report that I downvoted most of the comments replying to this line because they are not constructive: they fail to provide support for their claims, but their only claim is that other claims are unsupported. It's just short of trolling.

I'd really, really like not to argue this point in this thread, though. TFA is about a gym construction project, not a dietary intervention, and in any case, the role of "meat" -- which includes many, many different foods -- in the human diet is a complex scientific question which cannot be given a satisfactory treatment in a paragraph.

Instead, I hope to provide here useful, accurate resources that allow interested HNers to learn more about the topic. I preemptively acknowledge that I am not a qualified expert and there are considerable differences of opinion among experts. Let's start with "the problem":

http://www.sciencedirect.com/science/article/pii/S0002822304...

"Dietary patterns and health outcomes": "A systematic review of the literature on dietary patterns [...] was conducted. [...] Both of the currently used approaches for extracting dietary patterns have limitations, are subject to dietary measurement errors, and have not generated new diet and disease hypotheses."

Unfortunately, it turns out nutritional science is hard. Arguing about the age of studies on Wikipedia doesn't help us learn much. The largest study ever conducted on red meat consumption was the European Prospective Investigation into Cancer and Nutrition:

https://www.biomedcentral.com/1741-7015/11/63/abstract

I'm not going to post the result here: read for yourself. The fulltext is freely available. Red meat probably increases the risk of colon cancer:

http://preventcancer.aicr.org/site/PageServer?pagename=recom...

In the mid-20th century, there were concerns that things like phytate might be bad for you by sequestering nutrients. This one-time dietary "villain" turns out to prevent colon cancer:

http://www.ncbi.nlm.nih.gov/pubmed/8383315

These effects are both suspected to relate to mineral availability in the small intestine, or, as the researchers state, "Phytic acid forms chelates with various metals and suppresses damaging iron-catalyzed redox reactions." Red meat contains a lot of iron, hence, cancer.

Be careful reading nutrition studies, they can report strange things which may be spurious correlations. This Harvard School of Public Health study finds that chicken without skin is correlated with bladder cancer, but chicken with skin is not:

http://ajcn.nutrition.org/content/84/5/1177.full

I don't understand it either.

It is common informally to conflate the constellation of diseases represented by "cardiovascular disease" and that represented by "diabetes and metabolic syndrome". While there is a great deal of literature regarding the relation of meat consumption to the former, it is almost never even mentioned in connection with the latter:

http://en.wikipedia.org/wiki/Metabolic_syndrome#Etiology

Quick, do these studies contradict each other?

http://www.dur-a-avaler.com/wp-content/uploads/2013/02/Red%2...

http://ajcn.nutrition.org/content/94/4/1088.full.pdf

Answer: no. Whether red meat is healthier than "X" (here "nuts, dairy, and whole grains") is not the same question as whether it is healthy "in isolation", which really means "relative to other dietary constituents", which often include plenty of sugar and refined grains. Nuts, in particular, are known to be very healthy:

http://scholar.google.com/scholar?q=nut+consumption+health&b...

It's very, very easy to throw things like this at each other without really understanding the research you're looking at.

As for obesity, it turns out that fat both causes and prevents obesity:

http://ajcn.nutrition.org/content/68/6/1157.short

http://inspire.stat.ucla.edu/unit_15/NEJM2082.pdf

http://portalsaudebrasil.com/artigospsb/obes078.pdf

http://phdres.caregate.net/curriculum/pdf-files/nejm2k3-2074...

Note from the second study: "Adherence was poor
and attrition was high in both groups." The most effective diet is the one you actually follow. It should also be noted that the pro-fat studies tend to be experimental, while the anti-fat studies tend to be longitudinal.

The recent prevalence of large nutritional experiments represents, in my opinion, increased attention (and concomitant funding) directed towards nutrition research as obesity and associated metabolic syndrome have become a pandemic.

Shit be up in the air, yo. Anyone who claims to understand nutrition is a liar.

There are, however, low-hanging fruit: sugar is bad, vegetables are good, nuts are good, bologna causes cancer. There are various psychological analyses of diet patterns, but a common theme is that if you are constantly hungry you will give up on your diet or start eating more. I hope this is not too controversial: hunger causes eating. Try to pick foods that generate satiety.