Calcium is a mineral nutrient with vital roles in the metabolic process. Supplied in the form of soluble citrates, these minerals can be conveniently incorporated into nutritional beverages.
Citrate is naturally occurring substance in the body, a metabolic product formed at the beginning of the energy cycle. During the tricarboxylic acid cycle, carbohydrates, fatty acids and proteins are broken down to provide energy. Citrate is also important in plants where inorganic calcium and magnesium salts are taken from the soil and converted into their citrates. Several plant foods therefore contain these citrates.
Calcium Citrate:
- This is a bioavailable form of calcium, suitable for use as a supplement in enriched beverages and other food products where solubility is critical. Bioavailability describes the fraction of the nutrient absorbed by the body and available for further use.
- Since the 1930’s, when nutritional studies were done in Scottish school children, it has been generally accepted that adequate amounts of dietary calcium are necessary for normal bone growth and development in children.
- Since the 1970’s when osteoporosis became the subject of intensive medical research; the importance of adequate calcium nutrition particularly in postmenopausal women has been greatly emphasized. Extensive research has focused on whether calcium may slow or prevent age-related bone thinning. Most studies find that calcium supplementation does slow the loss of bone density, and numerous intervention studies document a decrease in fractures in postmenopausal women and older men given calcium supplements.
- The calcium Dietary Reference Intake for adults older than 50 was raised in 1997 from 1,000 to 1,200mg to reflect new information about calcium’s role in bone health2.
- High calcium intake also reduces the recurrence rate of colonic or rectal tumors, especially in women with high fat diets. Although no one is sure why calcium appears protective, it may be that it binds with potentially carcinogenic fatty acids and bile, rendering them harmless3.
- A recent study with 441 women found a 1,200mg calcium supplement decreased most premenstrual symptoms by 48%. It should be noted that the placebo group reported a 30% decrease in PMS symptoms4.
U.S. Calcium Dietary Reference Intakes, 19971
Group Adequate intake (mg/day)
Infants
Birth – 6 moths 210
6 months – 1 year 270
Children
1 – 5 years 500
4 – 8 years 800
Adolescents
9 – 18 years 1,300
Adults
19 – 50 years 1,000
Over 50 years 1,200
Pregnant & Lactation (no extra needed)
14 – 18 year s 1,300
19 & over 1,000
References:
- Patrick, L. Altern Med Rev. 1999 Apr; 4(2):74-85
- Sterling, M. Nutrition Science News, February 2000
- Hyman, J, Baron JA. 1998 Apr; 7(4):291-5
- Thys-Jacobs S, Starkey P. Am J Obstet Gynecol 1998 Aug; 179(2):444-52
