Alkalising Diets are all over the internet. All so called fitness experts and nutritionist are jumping on this bandwagon to sell their latest book, diet plans and miracle cures. But what is the reality here?
The Alkalising Diet – What is it?
This diet has taken people’s imagination by storm. It claims that all food when metabolized by your body leave behind either an acidic ash (residue) or alkaline ash. If you eat a lot of acidic ash producing foods, you are slowly shifting your body’s pH to be acidic and therefore can become host to a number of diseases including inflammation, weak bones (aka osteoporosis) and even cancer.
To prevent these diseases therefore, you should eat more alkaline ash producing foods. Here is a small list of acid and alkaline foods as presented by ionizeroasis .com:
If this happens to be true, this can be an amazing breakthrough in maintaining great health. Which is why I have spent a considerable amount of time pouring over research to really understand this acid-alkali ash business. There are two claims that I found very intriguing and it will help us also conclude if this diet has any substance. Here goes:
Claim 1: Acid ash producing foods cause calcium to leach from the bones making them weak:
There are two parts to this statement. One, that acid-ash producing food cause loss of calcium from bones and second that this weakens bones. Part 1 is true to an extent, so diets that are high in processed foods causes calcium to be released from the bones. The second part, that it weakens your bones is not true.
Here’s why: Your bones and teeth are the calcium reservoir for 99% of the body’s calcium. The remaining 1% calcium is used for body’s metabolic processes such as muscle function, nerve transmission, etc. The reservoir of calcium aka our bones are called upon repeatedly to maintain circulating levels of calcium at a constant (Ref1).
When a person takes a highly processed diet the increased sodium chloride is ‘neutralised’ by calcium increasing its presence in your urine (Ref 2). The body compensates for the loss of calcium through the urine by increasing the absorption rate of calcium in the gut and kidneys. Also the body uses up some from its reservoirs – the bones.
So how do the bones make up for lost calcium? The bones are constantly going through ‘remodeling’. As the calcium reserves falls in the body, calcium absorption rate is increased in the gut and kidneys through Calcitriol. The new calcium for your bones therefore comes through the diet. The body’s ability to increase calcitriol is therefore critical.
So, this is a misnomer that acid forming products causes osteoporosis as a research study specially looked at the alkalising diets claim to prevent calcium loss and it concluded that it is ‘not justified’ (Ref4). In fact the protein foods which are so called ‘acid forming’ actually improve bone healthy by increasing calcium retention and activating IGF-1 hormone, both of which stimulate repair of bones and muscles (Ref5).
Take-aways for us:
If you are eating a diet that consists of highly processed foods, make sure you are meeting your daily calcium requirements and have adequate phosphorus through adequate intake of fruits and vegetables.
Claim 2: Alkalising Diets prevent and can even cure Cancer
The Diet proponents claim that Cancer is formed if the body is in Acidic State. The truth is that our blood’s pH is tightly regulated by our bodies, mainly the lungs and kidneys to keep it slightly alkaline between pH of 7.35 and 7.45. No amount of whatever food you eat changes the alkalinity of your blood. If it did, you would be no your way to the hospital as untreated it can be fatal.
There are certain disease states in which your body is not able to regulate the acid in your diet. This can be due to an injury to the lung, liver failure, low blood sugar, drinking too much alcohol, overdose of sedative drugs, etc. But not from the food you eat. Read more about Acidosis here.
What food does is it changes the pH of your urine. The proponents of this diet will tell you to test the pH of your urine to convince you that the diet is working at alkalising your body. :/
Another truth is that the body has different pH levels all over. While the blood is alkaline as we saw above, the stomach is highly acidic with pH between 2 and 3.5 which is necessary to digest your food.
With respect to cancer, it is true that cancer cells thrive in an acidic environment but this is something they create for themselves and is the difference in how the tumour cells work with respect to the healthy cells in your body (Ref6).
And so, there is no evidence that any diet can change whole body’s pH or that it has any impact on cancer.
Take-aways for us:
Our blood’s pH is not something that any diet can change. When the body is not able to maintain the pH of the blood in its range it is an emergency situation which needs to be dealt with in a hospital. There is no evidence to support the theory that an acid heavy diet causes cancer.
In conclusion, the alkalising diet proposes eating more fruits and vegetables which is never a bad idea. As most of the food is low in calories, your overall calorie intake will go down and you might lose some weight while on this diet. It tells you to avoid processed foods, sugar and alcohol. Again, even if you are not losing weight, these are things that anyway you should consume sparingly.
The pitfalls include the fact that it demonises dairy and most high protein sources, excluding which which can be very detrimental to health. Everyone has a different capability to assimilate and process different foods.
For some people, having a low carb diet or dairy free diet or a high protein diet makes them feel good. This is something unique to an individual and it is healthy to experiment what does and does not work for you.
A diet is something that you can follow in the long term and which can be part of your lifestyle. Do not fall for these diet fads. Most times these are led by celebrity endorsements (by the way, this particular diet was popularised by Posh Spice a few years back). There are many people who have made million dollar empires riding the wave of the fad diets in season by selling pills, powders, books and special diet programs.
Being healthy and fit is not all that difficult. More on that coming soon 😉
Ref 1: Ross AC, Taylor CL, Yaktine AL, et al. Institute of Medicine (US) Committee to Review Dietary Reference Intakes for Vitamin D and Calcium. Washington (DC): National Academies Press (US); 2011.
Ref 2: Sellmeyer D E., Schloetter M, Sebastian A. Potassium Citrate Prevents Increased Urine Calcium Excretion and Bone Resorption Induced by a High Sodium Chloride Diet. Division of Endocrinology (D.E.S., A.S.) and the General Clinical Research Center (M.S., A.S.), University of California, San Francisco, California
Ref3: Breslau NA, Sakhaee K, Pak CYC 1985 Impaired adaptation to salt-induced urinary calcium losses in postmenopausal osteoporosis. Trans Assoc Am Physicians. 98:107–115
Ref4: Tanis R. Fenton, Andrew W. Lyon, et al. Meta-Analysis of the Effect of the Acid-Ash Hypothesis of Osteoporosis on Calcium Balance. Journal of Bone and Mineral Research. Nov 2011. Volume 24, Issue 11:1835–40
Ref5: Bonjour JP. Dietary protein: an essential nutrient for bone health. The Journal of American College of Nutrition. 2005 Dec;24(6 Suppl):526S-36S.
Ref6: Moellering RE, Black KC, Krishnamurty C, et al . Acid treatment of melanoma cells selects for invasive phenotypes. Clinical & Experimental Metastasis. 2008;25(4):411-25. doi: 10.1007/s10585-008-9145-7