BY: JOHN GLEESON
Feeling a bit unwell? Looking a wee bit peaky? Well there’s only one logical explanation for feeling this “under the weather”: obviously your blood pH is too acidic. According to pop-culture trends, the best cure for this is The Alkaline Diet. It’s a diet that’s been popularised by celebrities such as Alicia Silverstone and Victoria Beckham. As a 90s kid, having Cher from Clueless and Posh Spice endorse something means a big deal to me. The alkaline diet aims to balance the pH levels in your blood through dietary intervention and came into prominence from the naturopath Robert O. Young’s book “pH Miracle” I know it sounds crazy, and there’s no real scientific substantiation because you know….homeostasis is a thing. But celebrities have endorsed it so that’s something right? Wrong.
This diet is based on principals of acid ash producing foods (meat, poultry, cheese, fish and eggs) should be reduced and instead increase intake of alkaline ash producing foods, which are the majority of fruits and vegetables except cranberries, prunes and plums. “Acid Ash” categorisation refers to the pH of the ash of the food after combustion. The alkaline diet asserts that our blood is naturally slightly alkaline (basic), thus our diet should be mostly alkaline to mimic this. The proclaimed benefits of following such diet include weight loss, increased energy, and even the treatment of medical diseases…
However, the human body is already a fine-tuned system capable of maintaining blood pH levels between 7.35 and 7.45. A state of acidosis (blood pH falling below 7.35) can occur due to issues with the kidneys, while alkalosis (blood pH above 7.45) can occur due to severe bouts of hyperventilation. In healthy people, the acid-base homeostatic process keeps our blood pH levels normal- our dietary habits do not.
So what does the alkaline diet bring to the table?
Lots of whole fruits and vegetables…but for the wrong reasons. In this diet, foods such as meat, eggs, lentils, milk, caffeinated and alcohol drinks are to be avoided as they “acid ash”. The assumption of the alkaline diet is that over consumption of “acid ash” causes your body has to contend with more acid producing elements which makes body weaker. No need to fret though, you can eat all the “alkaline ash” foods you wish, including raw foods, plant proteins, fresh fruits, vegetables, and “alkaline water”.
If you consider what foods the alkaline diet recommends, it’s honestly a pretty healthy diet. However take heed. the claims this diet makes are unfounded and darn right misleading. For example, the pH throughout the human gastrointestinal system varies from 1-2 in the stomach, 5-7 in the duodenum (due to release of bicarbonate), then lingers around 6.5 through the jejunum, ileum and colon . Even in the small intestines, where there is a “microclimate” pH of around 6, dietary contents (upon reaching the lumen) have little influence on this acidic microclimate . The only things that truly have an effect on normal homeostatic state of the gut are inflammatory bowel diseases such as Crohn’s or coeliac disease which affect the absorption of nutrients. Ultimately, your diet barely affects the pH of your gut and, likewise, will not vastly influence your blood pH.
As it stands, very few studies have shown significant evidence in support of the alkaline diet’s claims. For that reason, health professionals do not recommend the diet. Actually, the alkaline diet is so dubious that it’s currently facing legal scrutiny due to allegations of its prescription as an unfounded, therapeutic treatment for serious medical conditions . However, all of us here at Science Meet Food definitely support the diet’s one redeeming quality: increasing your intake of fruit and vegetables! Consuming more nutrient-rich produce always a good idea, just don’t go thinking it’ll change the pH of your blood.
 G.B. Hatton, V. Yadav, A.W. Basit, H.A. Merchant, Animal farm: Considerations in animal gastrointestinal physiology and relevance to drug delivery in humans, J. Pharm. Sci., 104 (2015) 2747-2776.
 M.L. Lucas, B.T. Cooper, F.H. Lei, I.T. Johnson, G.K. Holmes, J.A. Blair, W.T. Cooke, Acid microclimate in coeliac and Crohn’s disease: a model for folate malabsorption, Gut, 19 (1978) 735-742.
 Business Insider – Alkaline Diet creator Lawsuit – http://www.businessinsider.com/alkaline-ph-diet-founder-arrested-2017-1?r=UK&IR=T