Guarana Energizer 900 mg By Source Naturals Overview & Drug Interactions

Calcium is a vital nutrient found in various foods such as dairy products, certain vegetables, and many fortified items. Over 99% of the body's calcium is stored in the bones and teeth, predominantly as hydroxyapatite. The remaining calcium circulates in the blood, extracellular fluid, muscles, and other tissues, where it is essential for processes like nerve signaling, muscle contraction, vascular activities, glandular secretion, and maintaining cell membrane and capillary permeability. It also plays critical roles in enzyme reactions, respiration, kidney function, and blood clotting, and is involved in neurotransmitter and hormone release, amino acid uptake, vitamin B12 absorption, and gastrin secretion. Calcium balance changes with age: it is positive during periods of growth, stable in adulthood, and tends to become negative in older age. Calcium loss occurs through feces, urine, sweat, and shedding skin cells. In women, reduced estrogen levels decrease calcium absorption and retention, increase bone turnover, and lead to lower bone mass. Calcium supplements come in various forms, including citrate and carbonate, which differ mainly in their calcium content and absorption rates. Calcium citrate is easily absorbed and can be taken without food, making it suitable for older adults or those with low stomach acid. In contrast, calcium carbonate, which contains a higher percentage of calcium, is best absorbed when taken with meals.

Guarana (Paullinia cupana) is a plant native to the Amazon rainforest in South America. The seeds of the guarana plant are used in traditional medicine and as a dietary supplement. Guarana is often marketed as a natural stimulant and is claimed to improve physical performance, increase energy and alertness, and reduce fatigue. It is sometimes added to energy drinks, weight loss supplements, and other products. Guarana seeds typically contain around 3-6% caffeine, although some extracts may contain far more. Guarana, when used in dietary supplements, is often standardized for its caffeine and tannin content.