There are other organs and systems in our bodies that help regulate blood cells. The lymph nodes, spleen, and liver help regulate the production, destruction, and differentiation (developing a specific function) of cells. Blood cells formed in the bone marrow start out as a stem cell.

The liver breaks down glycogen into glucose and releases it into the blood to maintain normal blood sugar levels. The liver stores vitamin A, D, E, K and B12. It also stores iron in the form of ferritin, which it releases so the body can make new RBCs.

5 nutrients that increase red blood cell counts

• red meat, such as beef.
• organ meat, such as kidney and liver.
• dark, leafy, green vegetables, such as spinach and kale.
• dried fruits, such as prunes and raisins.
• beans.
• legumes.
• egg yolks.

In the human adult, the bone marrow produces all of the red blood cells, 60–70 percent of the white cells (i.e., the granulocytes), and all of the platelets. The lymphatic tissues, particularly the thymus, the spleen, and the lymph nodes, produce the lymphocytes (comprising 20–30 percent of the white cells).

When your heart is beating too fast, it may not pump enough blood to the rest of your body. This can starve your organs and tissues of oxygen and can cause the following tachycardia-related signs and symptoms: Shortness of breath.

Your heart beats about 100,000 times in one day and about 35 million times in a year. During an average lifetime, the human heart will beat more than 2.5 billion times.

High resting heart linked to shorter life expectancy in stable heart disease patients, study suggests. Summary: If you are a person who already has stable heart disease, how fast your heart beats at rest can predict your risk of dying, not only from heart disease but all other causes, researchers say.

For every 1-bpm increase in resting heart rate above 70 bpm, participants had a 4-month shorter lifespan. Compared with having a desirable resting heart rate of 60 to 69 bpm, having a resting heart rate of 80 to 99 bpm was associated with a 5.6-year shorter lifespan in men and a 4.1-year shorter lifespan in women.

Bradycardia can be harmless, but in some cases it can be life-threatening. For certain people — mostly young adults and trained athletes—a slow heart rate is normal and doesn’t cause any symptoms or health problems.

Taller people have a lower resting heart rate compared to shorter people. A lower heart rate is generally associated with a longer functioning heart. In addition, larger diameter arteries are less likely to develop plaque build up on the Western diet.