I was just reading about some dietary issues, such as which foods help you loose weight and which foods can cause high blood pressure/heart disease etc, and I have a problem with the fact that much of the advice seems to be overly culturally biased, which I think poses an ethical issue.
For example, claiming that "pizza" (without specifying which sort) is a serious danger to your health may be true of American pizza, with all it's processed cheeses, processed meats, utra high fat and salt content, but REAL Italian pizza will never do anyone any harm: it is made with unprocessed, relatively low fat content cheese (fresh mozzarella has a high water content and hence low fat), lots of fresh veggies, and very little crust (ie, not even high carb), and rarely any meat at all, much less industrially processed meat! It has been eaten for millenia with little ill effects on the Mediterranean population, and on my last trip to Italy I ate pizza every day and lost weight in less than 2 weeks! Pizza, when made properly, is a very healthy wholesome meal.
Another example of culturally biased advice, is recommending salmon "twice a week" as a healthy food that can help you loose weight. Truth be told, this is only advised from the American perspective because Americans rarely eat fish at all (when in other cultures it is eaten every day) , rather than meat, and when they do it is most often salmon. Salmon is most often cultivated and filled with hormones and antibiotics, which would not be my first health choice (although I love it). The "twice a week" part about eating fish really gets on my nerves, as it implies in this context that the rest of the time one would be eating meat. As if there were no other fish choices other than salmon, as if it were not possible to eat fish, or vegetarian "alternatives" most of the time!
I have read many other advice articles on this site that have similar cultural biases, and for anything on the web, which by definition is viewed worldwide, I consider it unethical to be giving such biased advice to people seeking answers to medical problems.