Calcium - I found the perfect one for me.

I'm still searching EBSCOhost for more articles but finding exactly what we want to know isn't easy in a sea of information and articles. *LOL*


CALCIUM AND VITAMIN D

A National Institutes of Health consensus development

conference provided recommendations for optimal daily

calcium intake as follows: 1200 to 1500 mg for individuals

aged 12 to 24 years, 1000 mg for men, premenopausal

women, and postmenopausal women taking estrogen who

are in the 25- to 65-year age range, and 1500 mg for

postmenopausal women not taking estrogen and all persons

older than age 65 years.^' Calcium balance studies are

lacking in patients after bariatric surgery, but we follow

these consensus guidelines for calcium intake. In patients

with an intact digestive tract, elemental calcium from both

carbonate and citrate salts is well absorbed in tbe presence of

acid. In contrast, patients with aehlorhydria do not normally

absorb calcium carbonate unless they ingest the calcium with

food. Whether patients who have undergone RYGB absorb

calcium better as the carbonate or citrate salt (witb or witbout

food) is unknown. Initially, we recommend calcium carbonate

tablets with food intake because of ease of ingestion

(smaller tablet size due to 40% vs 21 % elemental calcium by

weight for the carbonate and citrate salts, respectively),

lower cost, and palatability if chewed. Flavored soft chewable

formulations of both calcium carbonate and citrate are

also available. Constipation associated with calcium carbonate

is uncommon after malabsorptive bariatric surgery. A

trial of calcium citrate is recommended if calcium carbon-

ate intake is not tolerated or is insufficient based on laboratory

results (ie, low 24-hour urinary calcium excretion in

the setting of normal blood levels of 25-hydroxyvitamin D

and parathyroid hormone [PTH]).

Vitamin D deficiency is most commonly due to inadequate

intake and is present in at least 20% of both obese

and nonobese individuals.^^" After bariatric surgery, vitamin

D deficiency occurs more often in patients who have

undergone malabsorptive procedures than in those who had

restrictive operations .'•^''The increased incidence may be

due to the length of the jejunoileal common channel.^' In a

study of 165 patients who underwent BPD, the incidence of

hypocalcemia was similar in those with a common channel

of 75 cm vs 100 cm, but the group with the shorter channel

had lower vitamin D levels and a higher rate of secondary

hyperparathyroidism (HPT)." Studies of biliopancreatic diversion

and DS-BPD have reported vitamin D deficiency

rates as high as 50% to 63%.^'-' Vitamin D insufficiency and

deficiency can be defined as total 25-hydroxyvitamin D

levels lower than 30 ng/mL and 15 ng/mL, respectively.

Although 25-hydroxyvitamin D levels higher than 30 to 40

ng/mL have been recommended for bealtby individuals,

mucb higher vitamin D concentrations may be needed to

achieve intermediate to nonnal levels of PTH, bone alkaline

phosphatase (BAP), and 24-hour urinary calcium after

bariatric surgery.

Reliance on any single test to assess calcium homeostasis

may be misleading. We screen patients with use of BAP

measurements, the least expensive and most convenient

screening test. We also monitor the serum total calcium

concentration, but calcium levels may be artificially low in

the setting of hypoalbuminemia because of the high binding

affinity of calcium to serum proteins. At 6 and 12

months postoperatively, and when otherwise indicated to

more fully assess the adequacy of calcium and vitamin D

intake, we monitor 24-hour urinary calcium and creatinine

levels and blood levels of BAP, 25-bydroxyvitamin D, and

PTH. Serum levels of PTH and BAP are usually increased,

whereas the urinary calcium excretion is decreased when

bodily stores of vitamin D are diminished. The goal of

calcium and vitamin D supplementation is to achieve intermediate

to nonnal serum concentrations of BAP and PTH

and 24-hour urinary calcium levels. The actual vitamin D

level is less important in this regard, given the wide range

of optimal 25-hydroxyvitamin D concentrations and the

assay variability recently noted among laboratories.^* The

most effective method of vitamin D supplementation after

RYGB is administration of large doses (eg, 50,000 IU) of

vitamin Dj (cholecaleiferol) or vitamin D^ (ergocalciferol)

once weekly and adjustment of the dosing frequency according

to 25-hydroxyvitamin D, BAP, and PTH blood

levels.