Alkaline Water: Benefits or BS?

Originally published on my blog, Girls Love Evidence, a home for evidence-based health and wellness.

Mentions of the benefits of alkaline water or an alkaline diet show up in a fair amount of health blogs and wellness columns. If you’re looking to end your stomach pain, try an alkaline diet and drink alkaline water. If you’re worried about your cancer risk, try alkaline water. Bone density, muscle loss, growth hormones, cancer, back pain, ditto. It’s become fairly ubiquitous as a cure for…well, whatever. Part of the reason it’s ended up everywhere is due to marketing language that’s just sciencey enough to seem legit, and fuzzy evidence that can be interpreted to back up some of these claims.

pH and Alkalinity

Before discussing ANYTHING here, I want to make sure that we are all on the same page regarding pH. pH is the measure of how acidic/basic a solution is. It’s measured on a scale from 0–14, with the more acidic items at 0, and more basic items at 14.

This scale isn’t random, instead, the 0–14 scale is describing the concentration of hydrogen ions (H+) in a solution. Hydrogen ions are produced from a substance that reacts with water. The more H+ ions are produced, the more acidic it is. On the basic side, a substance that reacts with water produces OH-, or hydroxide, ions. The more OH- ions produced, the more basic it is. There are multiple definitions of acids and bases, which you can read about here, but for common understanding, this is probably sufficient.

Our body produces H+ ions through multiple metabolic processes, including glycolysis (breaking down glucose to make energy) and ketogenesis (creation of ketones for energy when we lack sufficient carbohydrates). If our bodies are functioning normally, the amount of H+ ions is kept within a narrow limit, and no excess H+ is produced.

What this means is that for most people, excess build-up of H+ ions and excess acidity in the body is not a concern. There’s not a need to change the pH of the body with food or drinks, and your pH shouldn’t stray from the very tightly regulated ranges for each of your organs. (It usually doesn’t, because homeostasis is cool and keeps us alive, even when we subsist off of Mountain Dew and pizza).

Benefits of Alkaline Water and What The Alkaline Diet Gets Right

Part of the reason I first became interested in applying science to my life was that, for years, I struggled with undiagnosed gastrointestinal pain. I was otherwise healthy and had none of the risk factors for gastroesophageal reflux disease. Time and time again, research suggested that the reason for my pain had to do with too much acid in my GI tract.

There’s definitely some truth to this. An overly acidic diet is not a friend for those of us with heartburn. In general, it’s best to minimize the consumption of acidic items, carbonated beverages, or high-fat foods. This is called the GERD Diet.

Gastroesophageal reflux disease impacts almost a third of the US population, so it’s no wonder that introducing more alkalinity into the diet to neutralize some of the acid making its way out of the stomach might be a preference of many, and that they might notice the benefits of this diet on how they feel.

That said, the GI tract is very acidic — it needs to be in order to break down food. The GERD diet works in the same way as calcium carbonate (aka Tums), by increasing the pH and alkalinity. It doesn’t do anything to stop the acid from making its way up from the stomach (pH 1.5–3.5) into the esophagus (pH ~7), which is the cause of pain associated with acid reflux.

The alkaline diet and alkaline water are also thought to provide some benefit for maintaining bone density, but no studies to date show the benefits of alkaline water or an alkaline diet in bone disease. The only instance in which adding an alkaline substance may have a protective effect is if it is added to an overly-acidic diet consisting of excess protein.

Why The Alkaline Diet is Overhyped

I really wanted to find benefits here, but like in many other articles I’ve written, the science just doesn’t back up the claims. The effects of an alkaline diet and alkaline water are overexaggerated. What you eat just doesn’t have that much of an impact on your body’s pH and alkalinity.

This is a good thing, as the pH of our bodies should remain fairly constant, with a blood pH of 7.35–7.45 (already slightly alkaline). To be in good health, claims we need to be “alkaline” are therefore semi-legitimate.

However — if your blood pH were to become too acidic, it would probably be the result of diabetes, starvation, or excess alcohol intake. Essentially all of these cause ketoacidosis of some sort — the lack of energy or the inability to process energy that allows the body to break down fats. Without this energy, these fats end up in the bloodstream, and the blood pH drops.

If your blood pH does happen to exit that slightly alkaline 7.35–7.45 range, it is incredibly dangerous and would require a hell of a lot more than just fancy water to make any impact.

For the other claims about the alkaline diet/alkaline water, the evidence is equally murky. In cancer, there’s some evidence to show that tumors grow more aggressively in an acidic environment in mice and that by lowering the acidity, tumor growth is impacted. However, the treatment given to mice doesn’t work on humans. Other studies that have looked at the relationship between alkaline water/diet and cancer have too many external variables to show any kind of cause and effect relationship.

Regarding the benefits of alkalinity for chronic back pain, supplementation with alkaline minerals was shown to slightly alkalize blood pH and increase intracellular magnesium. This allowed subjects to properly absorb Vitamin D, which in turn, helped their back pain. Unfortunately, this study doesn’t show whether or not the alkalinity was responsible for this benefit, or whether it was a result of the increased magnesium.

Final Verdict on the Alkaline Diet and Alkaline Water

While there may not be any serious evidence of the benefits of alkaline water or an alkaline diet, the good news is that the food we eat doesn’t have much impact on our body’s pH. There isn’t much harm in adhering to an alkaline diet or drinking alkaline water.

If you feel like paying $20 for 12 waters (looking at you, Goop) or want to buy into the ridiculous MLM that has a $4,000 buy-in for an alkalizing machine, that’s your money, dude. Tap water is probably fine, though.