There are many myths about nutrition and health that swirl around the Internet, and regularly pop up in popular books and the mass media. One of the most pervasive is the notion that we should be striving to ‘alkalise our bodies’ in order to achieve optimal health and prevent cancer. Excess acidity, we’re told, is the root cause of every disease you care to name, from zits to cancer.
We’re supposed to micromanage our intake of alkaline and acid-forming foods, or take alkalising substances such as sodium bicarbonate, to make our bodies more alkaline.
So what’s the truth about our acid-alkaline balance?
(Side note for those who’ve forgotten their high school chemistry: acidity and alkalinity are measured using the pH scale, which runs from zero to 14. Zero is highly acidic, seven is neutral and 14 is highly alkaline.)
Like most myths, people who clearly have no understanding of human physiology promulgate this one. The question to ask is, “Which body compartment do you think you should alkalise?”
Surely not your stomach, which operates correctly at an acidic pH of around two, rising to about five after a meal; if the stomach becomes less acidic, we absorb less iron from our food.
Not your intestines either. Various digestive secretions carefully maintain the acidity of the small and large intestines helped by beneficial gut microbes, which produce lactic acid, short chain fatty acids and other acidifying chemicals from the foods we eat, in order to maintain the acidic environment required to prevent the overgrowth of pathogenic organisms.
The take-home message is that each compartment of the body has a pH range that is necessary for its proper function, and which is carefully maintained by a range of powerful mechanisms. You simply can’t ‘alkalise your body’, nor should you strive to.
However, the one little raindrop of truth in the murky waters of the popular discourse on acid-alkaline balance, is that you can make it easier for your body to maintain its optimal pH ranges through making healthy food and lifestyle choices.
For example, by eating a wholefood plant-based diet rich in fibre and resistant starch from vegetables, fruits, legumes and wholegrains, you’ll be providing your gut micro biome with the carbohydrates needed to produce the short chain fatty acids that help maintain optimal pH in the colon.
And to help maintain optimal bloodstream pH, you can choose a diet rich in alkaline-forming foods such as vegetables (especially green leafies) and fruits, while limiting (or eliminating) highly acid-forming foods such as cheese, meat, chicken and fish.
But don’t forget, you’re not ‘alkalising your blood’ by doing this. You’re simply taking the load off all those buffering mechanisms which have to work much harder to maintain optimal pH if your diet is high in acid-forming foods. Plus there are considerable health benefits, including a reduced risk of kidney disease.
So go ahead and stack your plate or bowl with health-promoting fruits and veggies – they’re beneficial for just about every element of physical and mental health – but please drop the silly notion of ‘alkalising your body’. Your body knows better than you what its pH should be.