Monday, December 1, 2008

Alkaline Food

Posted by Kirk
I spoke with my friend Awe lately about food as he used to be a food scientist. We were musing over hte fact that while there are a lot of acidic foods in our diets there are relatively few to no alkaline foods. This is easily explained by two important factors. First off, we like the taste of acidic foods. Foods with a low pH are acidic and create a sour taste. While in the extreme, sour is overwhelming, in moderation it provides the tangy bite in ketchup (acetic acids from the vinegar) and the tangy refreshing bite to lemonade (citric acid in the lemons.) The second factor to consider is a bit more practical. A low pH environment is good for food preservation. This brings up the interesting evolutionary question, "Do humans prefer acidic foods as an adaptive evolutionary strategy because tangy acidic foods are less likely to harbor pathogens?"

When trying to think of foods that are basic or alkaline, the only food he could think of was Lutefisk which is slightly alkaline. Not surprisingly, many people do not like the the taste of alkaline foods. Think soap.

I did a quick web search for alkaline foods and came up with this website.

This is a marvelous example of why you should always assume websites are written by hacks who understand very little science. This person recommends eating lots of vegetables which is probably a good thing but then goes on to say how fruits and vegetables are good alkaline foods. Want some examples? Here's what he has on his chart for foods that are "High Alkaline."

Lemons, Watermelon, Limes, Grapefruit, Mangoes, Papayas

Really? Really? LEMONS! LIMES? Lemons are one of the most acidic foods you can possibly find. Lemons have a pH of 1.8 to 2.3. For comparison, Battery Acid has a pH of 1.0 Any citrus fruit has a low pH due to the citric acid.

Moral of the story? Anyone can make a web page but that doesn't mean they know anything about science.