The Role of pH and Muscle Mass

This month I spent some time with MD’s Evan Centopani, filming his training session in his off-season. Besides noticing that Evan is looking like a beast, I walked into Evan’s house and noticed this small apparatus next to the sink that had some blinking lights on the side and was filled with water.

I said, “Evan, what the hell is that?”

Evan explained it was a water ionizer, which adjusted the pH of water. By using a water ionizer, it helped to create a more basic pH in the body, and reduce blood acidity. Evan explained that he had been doing a lot of reading on the role of pH and health. He is correct that pH has a profound effect on health, but also on muscle mass.

Having an acidic pH not only causes lower muscle mass, but can also lower plasma levels of IGF-1. Having an acidic pH is not conducive to building muscle. In fact, researchers make the blood more basic to counteract losses in muscle mass.

Interestingly, a mild but progressive metabolic acidosis occurs in elderly individuals who are exposed to a continuous challenge from acid-producing diets (e.g., diets relatively rich in meat and cereal grains compared to the fruit and vegetable content).¹ Oral administration of bicarbonate increases blood pH (makes the blood more basic) in a dose-related manner in healthy adults, both at rest and during exercise.² Metabolic acidosis has long been known to promote protein breakdown and nitrogen excretion.^3,4

In several studies, daily administration of bicarbonate— which acts as a blood buffer and reduces acidity— improved muscle power during intense exercise in healthy subjects.^4,5 However, the role of pH and muscle mass has never been clearly defined, so researchers set out to examine if blood pH has any effect on muscle mass.

Researchers from Tufts University examined 162 older adults and had them consume either a treatment with potassium bicarbonate, sodium bicarbonate, potassium chloride, or placebo. Remember that bicarbonates reduce blood acidity and promote a more alkaline environment. Interestingly, after three months of supplementation, only the bicarbonate altered the amount of acid production. The reduction in acid production resulted in less nitrogen excretion (greater protein retention) in men.⁷

In the men, the change in net acid excretion (the amount of acid being excreted from the body) was positively correlated with how much nitrogen was being lost. Although nitrogen excretion is not a specific indicator of muscle breakdown, in the setting of stable protein intake, exercise level, and bodyweight, a decrease in nitrogen excretion is consistent with decreased net muscle catabolism.

Treatment with bicarbonate significantly lowered nitrogen excretion. Therefore, using a blood buffer such as potassium bicarbonate may be a way of reducing muscle tissue breakdown.

Loss of muscle is associated with aging, but this occurs in conjunction with increased blood acidity. A possibility is that muscle wasting is influenced by the mild metabolic acidosis that occurs with aging. With muscle breakdown, amino acids released into the bloodstream provide substrate for the hepatic synthesis of glutamine. Glutamine is used by the kidneys to synthesize ammonia.⁶ Glutamine acts as a blood buffer when pH is acidic by being removed from muscle.

So Evan may be on to something good. It seems that drinking alkaline water or eating fruits and vegetables or using a bicarbonate supplement may prevent muscle tissue breakdown.

References:

1. Frassetto LA, Morris RC Jr, Sebastian A (1996) Effect of age on blood acid-base composition in adult humans: role of age-related renal functional decline. Am J Physiol, 271:t-22.

2. Douroudos II, Fatouros IG, Gourgoulis V, Jamurtas AZ, Tsitsios T, Hatzinikolaou A, Margonis K, Mavromatidis K, Taxildaris K (2006) Dose-related effects of prolonged NaHCO3 ingestion during high-intensity exercise. Med Sci Sports Exerc, 38:1746-1753.

3. May RC, Kelly RA, Mitch WE (1986) Metabolic acidosis stimulates protein degradation in rat muscle by a glucocorticoid dependent mechanism. J Clin Invest, 77:614-621

4. Mitch WE, Price SR, May RC, Jurkovitz C, England BK (1994) Metabolic consequences of uremia: extending the concept of adaptive responses to protein metabolism. Am J Kidney Dis, 23:224-228.

5. Edge J, Bishop D, Goodman C (2006) The effects of training intensity on muscle buffer capacity in females. Eur J Appl Physiol, 96:97-105.

6. Cersosimo E, Williams PE, Radosevich PM, Hoxworth BT, Lacy WW, Abumrad NN (1986) Role of glutamine in adaptations in nitrogen metabolism during fasting. Am J Physiol, 250:E622-E628.

7. Dawson-Hughes B, Castaneda-Sceppa C, Harris SS, Palermo NJ, Cloutier G, Ceglia L, Dallal GE. Impact of supplementation with bicarbonate on lower-extremity muscle performance in older men and women. Osteoporos Int, 2009 Sep 1.