Acid‑Base Balance: the “Best Controller” of the body… ever heard of it?

It is one of the most fascinating and least known mechanisms of the human body: acid‑base balance, the system that allows the body to stay healthy and function at its best.

Every cell, in order to live, produces acidic waste that must be eliminated or neutralized.
When this waste builds up, the acid‑base balance is altered and health is affected.

– Acidosis and alkalosis: two sides of the same coin

The body generates acids during the day, when it is more active and “metabolic”, and tends toward night‑time healing under conditions of greater basicity.
Acids, when in excess, are irritating and require large amounts of oxygen and mineral salts — which are taken from bones, teeth, hair and mucous membranes — weakening the defenses and promoting inflammation.

To rid itself of acids, the tissue activates a controlled inflammatory reaction, regulated by the adrenal glands and the release of cortisol.

– The circadian rhythm of acid‑base balance

The acid‑base ratio follows a precise rhythm, linked to the cortisol cycle:

• Acid phase: from 3 a.m. to 3 p.m.
• Basic (alkaline) phase: from 3 p.m. to 3 a.m. the following night

A cycle of about 12 hours, similar to a slow, vital pulse.
During the night, the body tends toward alkalosis and “heals”, releasing acids into the blood that are then neutralized.

– The different pH levels of the human body

Each physiological environment has its own characteristic pH:

Tissue / Fluid Average pH
Stomach 1.2 – 3.0
Vagina / Small intestine 3.5 – 4.2
Urine 4.8 – 8.0
Skin 5.0
Muscles / Oral cavity 6.2 – 7.2
Saliva 6.8
Blood / Cerebral fluid 7.35 – 7.45
Pancreas / Colon 7.8 – 8.0

This diversity is essential for maintaining overall balance.

– Acid‑Base Rhythm and Nutrition

Every time food is eaten, the acid phase is reactivated to support digestion.
If this happens during the basic window, metabolic processes slow down and fat accumulation is promoted, especially in a sedentary lifestyle.

Eating less — and at the right time — means living better.

Acid‑base balance is always involved, in the various tissues, in inflammatory dynamics. With every microbial, viral, traumatic or emotional attack, there is always necessarily a connective tissue inflammatory reaction, whose purpose is precisely to free the body from unwanted substances, whether material or immaterial. The 24 hours of the day are thus marked by a very specific circadian rhythm: Acid‑Base, in which the body alternates between an absorptive, acidic phase and a “catabolic” elimination, basic phase.

– Naturopathic tips for optimal balance

1️⃣ Eating in the acidic window (3:00 – 15:00)

In line with individual health conditions, it is possible to eat anything, in moderation, with particular attention to:

• salt (for people with hypertension)
• sugars (for people with diabetes)
• saturated fats (for people with high cholesterol)

From 15:00 onwards, avoid solid foods until 3:00 in the morning: the body enters the basic regeneration phase.

📊 Study from the Salk Institute (California)
Patients with metabolic syndrome who had dinner by 18:00 showed, after 3 months:

• reduced blood glucose
• reduced LDL cholesterol
• improved blood pressure

2️⃣ Intermittent fasting (14 – 16 hours between meals)

Allow the body time to use fat reserves and detoxify.
After a few days, ghrelin (the hunger hormone) adjusts and the feeling of well-being increases.

Documented benefits:

• Increased energy
• Enhanced immune function
• Liver detoxification
• Reduced cholesterol and blood glucose
• Diabetes prevention
• Weight loss
• Improved cognition and sleep
• Reduced cellulite and stretch marks 

3️⃣ Post‑meal walk (20 minutes)

After each meal, a brisk walk helps with:

• digestion
• glycemic control
• reduced fat accumulation

It can be done outdoors or at home, even on a treadmill.
Small actions, big results.

🌟 Conclusion: the harmony of the                       Acid‑Base rhythm

The body is a perfect machine, regulated by cycles of acidosis and alkalosis that alternate like day and night.
Respecting these rhythms means living in balance, preventing inflammation and rediscovering energy.

Whoever organized the “carousel of life” has provided, on the one hand, for the need to eat, and on the other hand still to “ensure” the potential “self‑destruction” of the body through the acidic processes of digestion. In essence, it is necessary to eat… to live, but while eating there is a move closer to… the end of life. A combination as spectacular as it is unsettling. So what then?

Eating at the right time, fasting with awareness and moving after meals: three simple rules for a longer, healthier and happier life.

Following the naturopathic path of
"… where Nature leads."

📚 ESSENTIAL BIBLIOGRAPHY

• Salk Institute for Biological Studies, Time‑restricted feeding improves metabolic health, Cell Metabolism, 2019.
• Guyton A.C., Hall J.E., Textbook of Medical Physiology, Elsevier.
• Garaulet M., Gómez‑Abellán P., Timing of food intake and obesity: a novel association, Int J Obes.
• Johnston J.D., Circadian rhythms, metabolism and obesity, Obesity Reviews.
• Asher G., Sassone‑Corsi P., Time for food: the circadian clock and nutrition, Cell.
• Lotti S. et al., Chronotype and eating habits in overweight/obese subjects, SINU 2023.

Good Life!

Heilpraktiker, Medicina naturale

Esperto in scienze alimentari e nutrizione

Dott. Gerardo Cappiello