The alkaline diet is a diet fad that started gaining popularity in around 2010, based on the notion that it's possible to alter your blood pH through a change in diet to make it more alkaline, receiving numerous health benefits. There is no scientific evidence whatsoever for the alkaline diet and there is no connection between the foods the proponents recommend and the actual pH of those foods. This craze is fueled by the fact that acidity and alkalinity are chemical concepts that people are likely to remember from school. In practice, the diet follows mainstream dietary advice mixed with high amounts of nature woo. Once someone has been convinced consuming alkaline substances is beneficial, that opens the door to selling them the hard stuff: coral.
The diet is also complemented by the belief that some people have that apple cider vinegar will cure all ills. They suggest ingesting six teaspoons of this acid every day will produce a more alkaline body pH. This idea is so ridiculous that it can only be described as scary.
The nugget of fact this idea is based on is that food can alter urine pH, which can reduce the impact of kidney stones; this is unrelated to your blood or the rest of your body.
Health benefit claims vary, but are as wide as:
Acids vs bases
Several lists identifying "alkaline" and "acidic" foods list lemons, limes and oranges as "alkaline", even though they are obviously very acidic. Lemon juice has a pH of 2, is corrosive to some metals and can damage tooth enamel if consumed excessively. Simultaneously, sodium salts of weak acids used as preservatives, such as sodium benzoate, will be always identified as acidic, even though they are in fact weakly alkaline. This disconnect betrays the fact that the "alkaline diet" is the same old nature woo dressed up in scientific-sounding terms that people are likely to remember from school, and has nothing to do with the chemical concept of acidity and alkalinity.
Some proponents of the diet attempt to circumvent the above problem by redefining the concept of acidity. Instead of testing the intact food, they burn it in air and test the pH of the resulting ash. The results of this procedure are trivial to predict: foods high in sodium, potassium, calcium, magnesium and other group I and II metals will come out alkaline, and foods high in phosphorus and sulphur will come out acidic. This crude process has absolutely nothing to do with human metabolism, and the results are completely uncorrelated with healthfulness of the tested food. For instance, unhealthy foods containing lots of sodium, fat and carbohydrates would be alkaline according to this test, while high-protein, low-sodium foods such as eggs and soy would be acidic due to high sulphur content.
A clue of the ineffectiveness of an alkaline diet is that whatever food you eat will (hopefully) pass through your stomach. The acidity of the stomach is affected by things such as stress, amount of food eaten, or infections. Eating acidic or alkaline foods has no effect on stomach pH, in much the same way as it has no effect on the pH of blood.
The main problem with the concept is that it is impossible to alter the pH of a patient's blood without causing severe health concerns. Mammalian blood contains a vast number of different pH buffers which evolved to automatically raise or lower the blood pH if a deviation occurs. These buffers keep the pH of human blood between 7.35 and 7.45. If the buffers become saturated and the pH of the blood is altered more than +/-0.4 pH, death will result. It is commonly claimed by alkaline diet proponents that cancer cells are killed in an alkaline environment, which is true, but so are almost all other cells in the human body.
Proponents will attempt to disregard the above by reminding us that it is possible to alter the pH of urine by eating or drinking particular foods. This is true, but is completely independent of the blood pH. This is based on the metabolites of certain food chemicals (referred to as "Ash") becoming concentrated in the urine. As a (healthy) bladder is an independent receptacle in the body, the pH of the fluid contained therein also has no effect on the blood pH. A different attempt at disregarding this is the claim that blood pH is balanced not by buffers but by excess acid being dumped from the blood into the cytoplasm of cells, meaning that blood pH won't reveal that your cells are dangerously acidic; needless to say, this is false.
More recently, proponents claim that the benefits arise from reducing acid load in the body. It is claimed that when acid load is too high, "alkaline minerals" such as calcium are reclaimed by the body from bones leading to conditions such as osteoporosis. Meta-analysis studies have shown this is not the case.
Far from being healthy, alkaline diets could actually be harmful, as they recommend removing certain food groups altogether rather than reducing certain types within the groups. Examples would be removing all fats and oils from the diet which provide Essential Fatty Acids, and dairy products, which are excellent sources of vitamins and minerals, especially vitamin D which is difficult to find in foods outside of dairy products.
As far as weight loss is concerned, a lot of patients will report a notable drop in body fat whilst following the alkaline diet. This is not, however, anything to do with the proclaimed method of action, and is instead because the diet classifies foods as either acid or alkali, and all acidic foods should be avoided. Browsing the list of acid and alkali foods, it should become instantly apparent that the foods to avoid are those classically associated with a high calorie diet (dairy products, fizzy drinks, confectionery, fast food, and just about all fats), and those marked as alkaline are generally fresh fruit, vegetables, nuts and seeds, especially when a ton of these are lower than blood's pH on the pH scale. If you avoid eating gobs of fat and sugar and otherwise keep the same lifestyle, your weight goes down - who'da thunk it?
Of course, with a new fad diet comes new expensive books and gadgets. On the top of the list are water filters or ionisers which claim to alkalinate drinking water and can cost several thousand pounds. Just adding some sodium bicarbonate to tap water is not sufficiently profitable.
Real Water® is claimed to have "millions of added electrons" which makes the water alkaline and improves cell hydration.
A blog entitled Real Water Health written by a Shelley Penney (a retired nurse interested in "health, peace and abundance") publishes many articles advocating the benefits of alkaline water. A list of 17 "Peer Reviewed Articles on Alkaline Water" is given on the site but while they all discuss research on acidosis, none of them mention any benefits from actually imbibing alkaline water. Shelley is not too hot on her chemistry as she claims "because it is very alkaline, ionized water may dissolve accumulated acid waste and return the body to a balance." Very alkaline products are caustic (e.g. drain cleaner); ionized water typically has a pH of 8 which is the same as sea-water. She further claims that "keeping our body fluid pH in an alkaline state may be the first line of defense in fighting any disease," as the body naturally regulates the pH of arterial blood between 7.35 and 7.45 you are likely to be dead before your blood stops being alkaline. As noted above, blood is a buffer solution which has the property that the pH changes very little when a small amount of strong alkali is added to it.
Ray Kurzweil sells alkaline water filters on his website. His transhumanist fans tend to gloss over this really obvious left turn into blatant alternative medicine pseudoscience, preferring to concentrate on his computer pseudoscience.
Consumers need to beware of such alkaline water schemes which encourage the sale of "alkaline water filtration systems" for the above-discussed health benefits. One such organization uses multi-level marketing or a pyramid scheme, which in some countries, like the US, is not illegal, but is highly frowned upon by the Federal Trade Commission due to the similarity to a Ponzi scheme. The reason is that the organization's sale structure is built upon recruiting new members with the promise of making large profits. These new members must "buy in" to the multi-level market scheme in order to sell the product or service to make these profits. With the promise of large earnings, many people are tricked into buying into the marketing plan, such as the case with Kangen alkaline water. Recruits are promised large profits yet must pay high prices to buy into the plan, they are also promised the many different health benefits of drinking the alkaline water, then after buying in they must also sell the product to new recruits in order to make the profit, the cycle then repeats. Overseas corporations like to use a multi-level marketing structure because it allows them to promote their product essentially for free (having members do the promotion for them) while maintaining a low profile making it very hard for governmental organizations to regulate then. The problem is that many of these companies and their products are overvalued and can be very hard to sell. In addition, the multi-level marketing plan has a tendency to collapse, just like Ponzi schemes, once the rate of new signups falls below a certain recruitment rate. Sellers of these alkaline water systems purport many health benefits yet there is a lack of scientific research to confirm the benefits. In addition, the sellers are not regulated by any governmental agency which may punish them for false or misleading advertising since each agent is an independent sales agent not affiliated with the host company other than they may receive a commission payment when making a sale. Many people in the US have fallen victim to this particular alkaline water filtration company's Ponzi-like scheme.
Quack Miranda Warning
Claiming a treatment will help treat cancer without concrete evidence is illegal in the UK under The Cancer Act 1939. Most of the sites promoting the alkaline diet have a Quack Miranda Warning on them to bypass legal problems such as this.
- Real Water Health - A pro-alkaline water blog by Shelley Penney
- The works of Waterworks4u - A particularly nasty account of how one water ionizer proponent, Peter Goodgold (who thinks that there exists only one disease, acidosis), operates and, in particular, deals with criticism.
- WebMD on alkaline diets
- Debunking The Alkaline Diet: Why The Celebrity-Endorsed Plan Doesn’t Work
- The pH values of some foodstuffs, (alkaline pH values are above 7).
- The Alkaline Diet Course Energise for Life (archived from October 16, 2012).
- How Can Adding Lemon Juice to Water Make the Water Alkaline?
- "pH Buffers in the Blood" - Rachel Casiday and Regina Frey Department of Chemistry, Washington University
- "pH Significance of Blood" - Newton BBS
- "Acid/Alkaline Theory of Disease Is Nonsense" - Gabe Mirkin, M.D.
- Causal assessment of dietary acid load and bone disease: a systematic review & meta-analysis applying Hill's epidemiologic criteria for causality
- InteliHealth: Can the alkaline diet be harmful?
- List of Alkaline Foods
- Alkaline Water Ionizers - energiseforlife.comimg
- Real Water Health: Peer-reviewed papers.
- Real Water Health: Ionized Water Is Alkaline
- The Cancer Act 1939
- "Energise for Life" disclaimer, displaying Quack Miranda Warning
- 3 Things You Need to Know About Raw Honey (Buying Tips) "An alkaline-forming food, this type of honey contains ingredients similar to those found in fruits, which become alkaline in the digestive system." Therefore, it's a health food.
- hiBeautiful. Skin Benefits of Raw Honey "With its natural pH level of 4.5, raw honey falls within skin’s naturally healthy pH range."