As a consumer in our health-conscious world, you may have come across a current fad: the alkaline diet (which may also be referred to using a combination of the terms acid or ash). Fancy name, but what does it mean?
The alkaline diet holds the assumption that, if we only eat optimal pH foods, the pH level of the fluids in our bodies will optimize in response, thereby protecting our organs and systems from damage and disease and improving our general health.4 But how realistic can that be? Is there evidence that this strategy works, or should we have left the alkaline diet in 2018?
So, how does your body’s pH affect you?
Your blood and your urine have a pH level ranging from 0-14, where 0 is most acidic, and 14 is most alkaline. Evolutionarily, your body maintains its pH level very tightly (typically between 7.35 and 7.45 in blood), as a pH even slightly outside this range can be incredibly harmful to the body. The variability within this range depends on time of day, diet, timing of meals, when you use the bathroom, how quickly you are breathing, and many other factors.4 The crux of the alkaline diet is that when the body's pH is on the higher end of this range (more alkaline), it is better able to absorb and use vitamins and minerals.
How did this diet become so catchy?
Currently, the average American’s diet is high in sodium and low in essential minerals like potassium, magnesium, and calcium. And, as luck would have it, these essential minerals promote an alkaline environment in the body, priming it for enhanced absorption of a wide range of other vitamins and minerals. So, the alkaline diet theorizes that, if we eat foods high in these minerals, our bodies' absorption of healthy nutrients would rise, thereby making us healthier and stronger. But is that the right assumption to make? Let's dive into the science.
What foods does the alkaline diet promote?
Fresh fruits, vegetables, and unprocessed plant protein foods are all alkaline-diet-approved. The biggest bang for your buck is dark leafy greens such as spinach, and kale, which are most alkaline.4
Perhaps counterintuitively, the alkaline diet also promotes foods which are inherently acidic, but appear to promote an alkaline environment in your body once you digest them. This includes lemons and raw apple cider vinegar.
The alkaline diet discourages more acidic foods, including highly processed foods such as meats, grains, and other high-sodium packaged foods. Dairy, eggs, alcohol, and caffeine also don't make the cut.4
What are the claims and what is the truth?
The alkaline diet claims to elicit many health benefits. Here is the breakdown of each health claim and what the literature has (or hasn't) proven.
1. The alkaline diet can increase bone density and vitamin absorption
Proponents of the diet claim: The alkaline diet is high in many minerals essential for bone strength, such as magnesium and potassium. When our bodies have a higher pH, we have the potential to absorb these minerals better. The more nutrients that are absorbed and retained by the body, the more will be deposited into the bones, thereby strengthening them.
InsideTracker thinks: While this theory is supported by science (minerals consumed= minerals deposited in the bones), there are many mechanisms involved, and we cannot conclude that alkalinity is to thank. Yes, the alkaline diet promotes dark leafy vegetables, and yes, dark leafy vegetables promote bone strength, but to assume that the connection rests entirely on the pH of these foods ignores their chemical complexity:
Leafy greens are a good source of calcium, which goes directly into building bones. They also contain vitamin C, which acts as an antioxidant to protect your bones from cell damage.1,3 Potassium is also present in high amounts in vegetables, and it can help to promote the absorption of calcium, rather than it being excreted. Finally, high levels of magnesium in these foods help to convert Vitamin D into its active form, which goes onto 'turn on' calcium absorption and prevent mineral loss from your bones.
Takeaway: It is the calcium, magnesium, potassium, and Vitamin C within foods that the alkaline diet promotes that increases bone mass, rather than the pH of the foods.3
2. The alkaline diet is associated with a lower risk of disease
Proponents of the diet claim: The alkaline diet can lead to a decrease in inflammation. Inflammation is a marker of many diseases, including hypertension, cardiovascular disease, reflux and GI diseases. Processed foods are associated with an increase in the body’s inflammatory response, and the alkaline diet restricts these foods.4
InsideTracker thinks: There are studies that show an alkaline diet can be beneficial in reflux disease, hypertension, and other diseases. Reflux disease, or acid reflux, is when the acid in your stomach reaches your esophagus. Following an alkaline diet can help to inactivate pepsin (an acid-loving stomach enzyme) and buffer HCl, a stomach acid that is overproduced in people with reflux disease. This will decrease the amount of acid available to reach your esophagus and cause irritation.2 Red and processed meats, alcohol, and refined grains refined grains area all associated with inflammation. Reducing the intake of these can help to reduce inflammation.
Takeaway: Red meat, processed meat, alcohol, and refined grains are all associated with increased inflammation at high intakes. Reducing these items in your diet can help to reduce inflammation, regardless of pH level.
3. You can buy and drink alkaline water to prevent an acidic pH in your body
Alkaline water is a commodity water that has a slightly higher pH than regular bottled water. This is achieved through the addition of the electrolytes calcium, magnesium, and potassium. In theory, it makes sense that alkaline water can benefit health by reducing acid load and preventing fatigue. However, there is no scientific evidence to prove that drinking alkaline water will improve performance.2 The ambiguity is due to the fact that consuming electrolytes that are in alkaline water through the diet or other supplements may be responsible for the benefits, and not just the water itself.
So, what do we think?
Strictly following the alkaline diet because of its theoretical impact on altering your body's pH is not scientifically sound. If our bodies couldn't manage pH level, we wouldn't be able to survive! Products that promote bodily pH change are not based in science.
In addition, the alkaline diet is very restrictive in nature. Highly restrictive diets are shown to have low rates of long-term compliance. However, the alkaline diet is comprised of many food that we at InsideTracker regularly recommend to our users and believe will help to optimize your biomarkers. A diet that is high in fruits and vegetables and low in processed foods can help you in many ways, but the restrictive nature of the diet and the hyper-focus on foods' alkalinity is not necessary to achieve optimal health.
References
Chin, K.-Y., & Ima-Nirwana, S. (2018). Vitamin C and Bone Health: Evidence from Cell, Animal and Human Studies. Current Drug Targets, 19(5), 439–450. https://doi.org/10.2174/1389450116666150907100838
Koufman, J. A., & Johnston, N. (2012). Potential benefits of pH 8.8 alkaline drinking water as an adjunct in the treatment of reflux disease. The Annals of Otology, Rhinology, and Laryngology, 121(7), 431–434. https://doi.org/10.1177/000348941212100702
Osteoporosis Diet & Nutrition: Foods for Bone Health. (n.d.). Retrieved January 16, 2019, from https://www.nof.org/patients/treatment/nutrition/
Schwalfenberg, G. K. (2012). The alkaline diet: is there evidence that an alkaline pH diet benefits health? Journal of Environmental and Public Health, 2012, 727630. https://doi.org/10.1155/2012/727630