Monday, May 14, 2012

Proteins, Protein Isolates, and Amino Acids

Protein isolates are rich in amino acids; note the word “acid”. Isolated proteins are acid-forming (systemically acidic), regardless of whether the whole plant may be alkaline-forming. Hence, brown rice protein isolate is a product isolated from brown rice; hence, it is no longer whole brown rice since the germ and fiber are removed, and is now rich in acid-forming protein. It is no longer an alkaline whole grain as the name, and product marketing, may imply. The same logic would apply to other protein isolates. If only whole grain powders are used, without protein concentration or isolation, the alkaline-forming claim would still be reasonable; otherwise not so.

Raw proteins are typically harder to digest than cooked ones, but that depends on how much the heat denatures the proteins. Denaturing = digestion and is normally necessary to make the amino acids bioavailable and to reduce the likelihood of developing food sensitivities due to incomplete digestion triggering immune (IgG) reactions. There is nothing wrong with denaturing proteins, unless you are trying to preserve certain structures like immunoglobulins in whey protein. But the nature of whole plant foods is to lock up nutrients by binding them in a food matrix, requiring a process of digestion, or denaturing, to separate them from their food matrices for optimal absorption from the gut. It is also questionable exactly how “raw” these proteins are. Some companies ferment so-called raw materials and only count the presence or absence of heat after fermentation when labeling them as “raw”. This may be as inaccurate as labeling yogurt with live cultures as “raw” even if pasteurized milk was used as a sterile culturing medium.

There is some evidence that animal proteins can better promote cancer growth (The China Study) than plant-based proteins, but otherwise are considered excellent protein sources.

Plant proteins each have their own issues: Rice protein tends to have heavy metal contamination. Chia protein is very gummy and thus hard to use in a liquid mixture intended for drinking. Hemp protein doesn’t taste very good. Etc.

Protein digestion is obtained by actions of stomach acid (low pH) and enzymes both in the stomach & intestines (pancreatic protease). In the acidic environment of the stomach, the negatively charged side chains are removed by pepsin. In the stomach, Pepsin helps to "unwind" the proteins and breaks the bonds between the amino acids in certain places. In the more alkaline environment of the intestine, the positively charged side chains are removed by trypsin. In the small intestine, other enzymes break the bonds between different amino acids that pepsin can’t break. Because proteins are such complicated molecules, it takes a long time and more than one enzyme to completely digest them (break them down into amino acids). Digestion results in about 60% small peptides (or peptide-bound), which are chains of amino acids, and 40% free amino acids (or free form). Peptides can be further broken down by hydrolysis in enterocytes (intestinal absorptive cells, simple columnar epithelial cells found in the small intestines and colon).

Plant enzymes (proteases) can also digest protein in a wider range of pH, to help compensate for low stomach acid. But plant enzymes don’t compensate for other functions of stomach acid:

  • Acidic immune barrier
  • Environment to promote Acidophilus (literally: ”acid loving”)
  • Digestion (liberation) of minerals from food, water, and non-chelated supplements
  • Digestion (liberation) of vitamins from food matrices

Friday, May 04, 2012

Natural Controversies: Free Webinar May 15th at 7 PM (CT)

I'm giving a free public webinar May 15th 7 pm CT on Natural Controversies. Register here: and use this code for free registration as my guest: SPKGST5629

We’ve all seen contradictory information about natural health products. Sensational reports may depict certain ones as always good or bad for us, but these are often based on inaccurate information. A combination of ignorance, bias, and other errors contribute to this mass confusion.

Take a look at the scientific data that reveals the truth behind some Natural Controversies:

  • What are some of the dieting secrets that work long term?
  • Some experts claim that all sugars are the same to the body; others claim that certain sweeteners like fructose are bad for you. What’s good and bad about fructose and how does it work in the body?
  • Aren’t the vitamins and minerals in food better for us than the forms commonly used in dietary supplements?
  • A few years ago, doctors routinely warned us against taking high doses of vitamin D but now it’s the latest thing.
    • How much vitamin D is considered healthy?
    • What are the safety limits?
    • What is the difference between its forms, D-2 and D-3?
  • Some fish oils are in a triglyceride form while others are in a form called ethyl esters. What are the differences and benefits of each form?
  • Soy foods are highly controversial; with some health gurus warning against its use and others promoting it as an important health food. What does science tell us about the safety of soy foods versus their potential benefits?

• Vitamin E had been touted as important to cardiovascular health until recent studies questioned its safety. Is it safe, at what levels, and why is there so much controversy over this basic essential nutrient?

• Are stearates hydrogenated? Bad for us?