1. Increased oxygenation

When air passes through the nose, large amounts of nitric oxide are produced, which dilates the blood vessels in the lungs and allows more oxygen to be transferred to the blood. Oxygen, in turn, is crucial for your body to efficiently produce energy and for your cells to function optimally, ultimately supporting your immune system.

2. Promotes detoxification 

When you breathe deeply, the diaphragm, a muscle just below the lungs that assists in pumping air in and out during deep breathing, moves up and down. This action massages, among other things, the liver and lymphatic system, which work to eliminate toxins and harmful substances from your body, thereby promoting health and well-being.

3. Stimulates antibodies 

When you breathe deeply, it helps the body to create a good pH balance. This enhances the function of antibodies used by the immune system to detect infections, allowing infections to be disarmed more quickly and efficiently.

4. Reduced oxidation

When you breathe incorrectly, you take in too much oxygen relative to carbon dioxide. Even though it may sound contradictory to what you've heard before, the body needs a certain amount of carbon dioxide to keep blood vessels supple and assist oxygen in entering cells. 

When you have an excessive amount of oxygen compared to carbon dioxide, free oxygen radicals are formed, leading to "rusting" effects. To address the damage, the body increases the level of inflammation, putting a strain on your immune system. With proper breathing, oxidation (the "rusting" process) decreases, consequently reducing the amount of inflammation.

5. Warms inhaled air

Inhaling cold air through the mouth strains the trachea, prompting the immune system to repair damage. Breathing through the nose allows air to be warmed and filtered through your nose hairs, enabling the immune system to focus its energy elsewhere.

6. Decreases fundamental stress

The body has an innate ability to always prioritize what is essential to keep you alive and, to the best extent possible, optimize your health. Since we can only survive for a very short time without oxygen, the body will always prioritize getting as much oxygen as possible to your cells. 

Breathing improperly results in both insufficient oxygen intake and requires your body to exert extra energy to distribute oxygen to different body parts. This stresses your body and can eventually lead to exhausted adrenal glands as they need to produce large amounts of cortisol to suppress inflammation. Deep breathing ensures your body receives an adequate supply of oxygen, allowing it to allocate energy to other functions, thereby reducing the foundational stress in your body.