Acid or Alkaline Diet

I always hear about using diet to control the pH of our body. Some people claim it helps in weight loss and detoxification; others say it can cure cancer. Patients tell me of friends and direct sellers promoting “alkaline water”.

What is pH? It is a measure of how acidic or alkaline a substance is:

  • 0 – 7 is acidic
  • 7 is neutral
  • 7 – 14 is alkaline

The pH value varies within our body. Some parts are acidic; others are alkaline. Our blood pH, for instance, stays within the narrow range of 7.35 to 7.45, making it slightly alkaline. But our stomach is loaded with hydrochloric acid, giving it a pH value between 2 and 3.5 – very acidic.

Yes, we can analyze food and place food into acidic, alkaline, or neutral categories when the food is outside our body. Once ingested, however, the pH of the food becomes irrelevant because the acidity or alkalinity will change as the food passes through the digestive tract. Upon digestion, the nutrients will be absorbed into our bloodstream and the pH will again differ.

I don’t think diet can manage the pH in our body. Why? That’s because our body has a mechanism to regulate the pH in the body. This is known as Acid-Base Homeostasis, sometimes known as “the buffer system”. Any rise or fall in acidity or alkalinity in the body will be quickly managed by the buffer system. The process is controlled by our brain – hardly influenced by the food we eat.

It remains controversial whether controlling the pH of the body can control the growth of cancer cells or not. For cancer patients who are undergoing conventional treatment, I recommend looking into the calories and protein content of the food rather than the pH!

Further reading:

Acid/Alkaline Diet for Cancer? The Evidence, or Lack of. 2011 by Julie Lanford MPH, RD, CSO, LDN. www.cancerdietitian.com

Marcus Lee, Dietitian