If you’ve heard of the alkaline diet, you probably know its biggest supporters are celebrities such as Victoria Beckham, Jennifer Aniston, and Kate Hudson. I was curious as to why these A-listers were fans, so I looked into the science to better understand this trend.
Celebrities may gain fame for an acting role or a hit song but oftentimes become role models for lifestyle choices. We look to them for how to dress, style our hair, and where to go out at night. It’s not surprising that we’re also curious about what they eat.
Plenty of celebrities have endorsed diets or credited diets for their successes. For example, Oprah has championed WW (the new Weight Watchers) for years, Kim Kardashian has been known to follow Atkins, and Tom Brady has published his own diet called The TB12 Method.
The Alkaline Diet
So, what makes the alkaline diet different? To begin with it has a scientific ring to it. If anyone remembers high school chemistry, you may recall that the pH refers to the acidity or alkalinity of something. It is measured on a pH scale of 0-14. An alkaline substance has a pH greater than 7 while pH of an acidic substance is less than 7.
Each living thing has a unique pH. For example, 6-7 is the ideal pH for soil and 8.1 is optimal for the ocean.
The pH of the Human Body
When people talk about acid-base balance in the human body, they usually mean the pH of serum, or blood. There is a very narrow window of normal pH balance for all humans – which is around 7.3-7.45 – to survive.
But, different areas of our body have different pH levels, depending on their function. For example, the stomach is more acidic with a pH of 1.3-3.5. This makes it possible to digest food and ward off unwanted microorganisms. By comparison, the pH of skin is 4.5-6.
How Does the Human Body Regulate pH?
The lungs and the kidneys do an impeccable job at keeping our pH levels balanced. The lungs remove carbon dioxide (a mildly acidic waste product) through breathing and the kidneys remove acids through urination.
Luckily, pH is not something we have to think about or control with any modified behaviors. Our body knows how to keep our pH balanced, just like our heart knows how to keep a beat.
Why Would We Want to Alter this pH Balancing Process?
The theory behind the alkaline diet (also knows as the alkaline-ash diet or acid-alkaline diet) is that when certain foods are digested, they leave behind a residue that either decreases, increases, or leaves a neutral impact on pH.
What Foods Are High-Alkaline Promoting?
Foods that produce more alkaline residue are fruits and vegetables. These would be foods to choose from on an alkaline diet.
What Foods Are High-Acid Promoting?
Foods that produce more acid include eggs, meats, and dairy. These would be foods to avoid, in addition to coffee and alcohol.
Foods that are considered neutral are fats and sugars. These can be eaten occasionally on the alkaline diet.
Some versions of the program recommended avoiding wheat products, legumes, nuts, and seeds. The discrepancy is likely due to the fact that we cannot be entirely certain how each food breaks down in every individual.
With so many foods that need to be restricted or limited, it can be complicated to navigate and challenging to meet nutritional needs.
What’s the Concern Behind Acid-Producing Foods?
It has been hypothesized that foods causing a decrease in pH can be harmful to our health, or make us more vulnerable to disease. But there is a lack of research to support this.
Regardless, whether food impacts our pH or not, a diet high in fruits and vegetables is health promoting, and may be what these celebrities actually find appealing in this alkaline diet.
Are Alkaline Foods Helpful in Cancer Treatment?
Though there are hundreds of studies that have been conducted, there are no strong studies that show eating an alkaline diet has any impact on cancer prevention or treatment.
The only robust study on the topic specifically focused on alkaline water (not alkaline-producing foods), and the results reinforced that there are no associations between cancer treatment and drinking alkaline water.
My mom had cancer and underwent treatment for years before she passed away. I know just as well as anyone that it’s in our nature to look for ways we can control cancer, to grasp at whatever we think may help. I used to encourage my mom to eat all sorts of concoctions – it’s a very natural instinct.
But individuals with cancer have their own unique needs. There is no cure-all cancer diet. The one blanket recommendation for nutrition and cancer is to maintain strength with adequate nutritional intake. This can be challenging to do while sick, and is made more challenging when certain foods are off limits.
Does the Alkaline Diet Help with Reflux?
Foods that exacerbate acid reflux are acidic foods (tomato and citrus fruits for example). These foods produce an alkaline ash and would be allowed on the alkaline diet. Therefore, this diet would likely exacerbate reflux symptoms.
What about Bone Disease?
A causal association between dietary acid load and osteoporotic bone disease is not supported by evidence from clinical trials. On the other hand, adequate calcium intake, Vitamin D sufficiency, and movement are proven to help keep our bones healthy.
Does Alkaline Water Prevent Bone Disease?
There is no evidence that alkaline water has health benefits. The FDA has denied companies the ability to claim health benefits related to bone health on alkaline water packaging. Regular water is the best way to hydrate – and it’s much cheaper!
Does Alkaline Water Benefit Athletes?
In one study of 100 healthy adults from 2016, drinking alkaline water after a workout was associated with a decrease in blood viscosity during the recovery phase. This is one small study using one type of hydration marker, but is not the only way to measure or assess for rehydration. Meaning, drinking alkaline water after a workout will not guarantee faster rehydration than regular water.
To put this into perspective – high performance athletes often have their own specialized diet plans (and in Tom Brady’s he has a team of people assessing his every move!) specific to their sport or position on a team. Their nutritional needs are different than ours.
In situations where your body experiences acute pH swings due to extreme fluid loss (think sweat, diarrhea, and vomiting) your body will eventually self-correct itself through adequate rehydration and/or electrolyte repletion (Gatorade anyone?).
What Medical Conditions Impact pH?
In more chronic conditions, pH balance can be out of whack for prolonged periods of time. This requires medical treatment and cannot be prevented or cured with an alkaline diet. Here are some examples:
- In unmanaged diabetes, if insulin can’t bring sugar into the cells, the body will make ketones that contribute to a build up of acid in the blood. This is called Diabetic Ketoacidosis (DKA) and requires medical intervention. Blood sugar control will prevent this from happening.
- In COPD or other lung conditions, carbon dioxide cannot be removed properly and this contributes to low blood pH.
- In Chronic Kidney Disease (CKD), kidneys can’t manage the process of excreting acid in the urine. Lower protein diets or oral sodium bicarbonate are typically recommended to slow CKD progression.
THE BOTTOM LINE
The alkaline diet centers around eating mostly fruits and vegetables. A diet high in fruits and vegetables is health promoting and not inherently problematic, but a specific alkaline diet restricts or limits many other food groups that provide us with nutritional variety.
The reasoning behind the Alkaline Diet is flawed, and not backed by science. What we eat will likely not change our pH balance.
Following any sort of restrictive diet, including the alkaline diet, to treat disease makes meeting nutritional needs challenging. Though understandably intriguing, this can cause more harm than good.
It’s interesting to learn more about how celebrities like Tom Brady stay so fit – but in reality, emulating someone else’s dietary patterns may not yield the results we were hoping for. And as always I welcome your comments and questions!