Dietary Sources of Calcium / Coral calcium / InformationXchange at StuartXchange

Approximately 1000 mg of calcium is ingested daily in the diet. About 800 mg appears in the stool from unabsorbed dietary calcium and intestinal secretion) and 200 mg in the urine. The percentage of dietary calcium absorbed increases or decreases, influenced by dietary intake and the adaptive effects of vitamin D and parathyroid hormone.

The recommended daily allowance (RDA) is 700 to 800 mg (0.7 to 0.8 g) per day. Some people remain in balance on lower intakes. The WHO recommends only 400 to 500 mg per day for adults. Because of increased calcium excretion higher in high protein diets, a higher calcium intake is recommended. For pregnant and lactating women, 1200 mg daily is advised; and 1200 to 1500 mg for women over 50.

After age 40, the calcium requirement increases as the efficiency of intestinal calcium absorption progressively declines. Postmenopausal women and most elderly men must increase their intake 50% to adapt to changing needs and to avoid negative balance.

Calcium is found almost exclusively in three classes of foods - milk and milk products, green vegetables, and a some fish and shellfish. In terms of calcium per 100 kcaloris, green vegetables seem to be an excellent source. However, there is an uncertainty as to its absorption from green vegetables.

Milk is an excellent source, because of its calcium absorbability. However, to obtain 1500 mg of calcium from milk, it will require an intake of more than 5 cups, providing about 90 calories per cup of nonfat milk - or 450 calories per day. Alas, to the calorie-counting dieter.

DIETARY CALCIUM SOURCES

FOODS RANKED BY CALCIUM PER SERVING AND CALCIUM PER 100 KCALORIES

CORAL CALCIUM

CALCIUM SUPPLEMENTS AND BIOAVAILABILITY: THE ACID TEST

VEGANS DON'T NEED DAIRY FOR GOOD BONE HEALTH

D I E T A R Y S O U R C E S
A Simplified Comparative Table

SOURCE	CALCIUM (MG)
MILK (1 CUP) Non-fat Low-fat, 2% Whole, 3.3% Buttermilk	302 297 291 285
CHEESE (1 0Z) Swiss Cheddar Mozarella, skim American Blue Cottage, low-fat (1.2 cup)	273 205 183 163 150 77
YOGURT, PLAIN (8 0z) Nonfat Low-fat Whole	452 415 274
FROZEN DESSERTS, VANILLA (1 cup) Yogurt Ice cream Ice milk	249 176 176
SEAFOOD (0z) Sardines, with bones (4) Salmon, pink, canned (6) Oysters, fresh, raw (8) Shrimp, canned (3) Lobster (3)	496 333 213 96 55
NUTS (cup) Almonds (1/2) Brazil (1/2) Peanuts	152 130 104
VEGETABLES (cup) Mustard greens (1) Okra (1) Broccoli (1) Turnip greens, raw (1/2)	193 147 136 126

FOOD ITEMS	Calcium per serving (mg)	KCalories per serving	Calcium per 100 KCal (mg)
Sardines, canned w/ bones	371	175	212
Kefir - 1 cup	350	160	219
Goat milk - 1 ciup	326	168	195
Shrimp. boiled - 3.5 oz	320	109	294
Non-fat milk + solids - 1 cup	316	91	347
1% milk + solids - 1 cup	314	105	299
Romano cheese - 1 cup	302	110	275
Nonfat milk or yogurt	302	86	351
1% low fat milk - 1 cup	300	102	294
Whole milk - 1 cup	291	150	195
Buttermilk - 1 cup	285	99	288
Chocolate milk, while - 1 cup	280	210	133
Swiss cheese - 1 oz	272	107	254
Spinac h, canned - 1 cup	271	50	542
Spinach, cooked - 1 cup	244	41	595
Cheddar cheese - 1 oz	204	114	179
Munster cheese - 1 oz	203	104	195
Oysters, raw - 1 cup	202	160	126
Turnip greens, cooked - 1 cup	198	29	683
Broccoli, cooked - 1 cup	178	146	387
Salmon, canned, with bones - 3 oz	167	120	139
Beet greens, cooked, 1 cup	165	40	413
Bok choy, cabbage, cooked - 1 cup	158	20	790
Cottage cheese, lowfat, 2 % - 1 cup	155	205	76
Dandelion greens, cooked, 1 cup	147	35	420
Soy beans, cooked dry - 1 cup	132	235	56
Collards, cooked - 1 cup	113	20	165
Tofu soybean curd - 1 block	108	86	126
Mustard greens, cooked - 1 cup	104	21	542
Parsley, chopped fresh - 1 cup	78	20	390
Almonds, whole dried -1 cup	75	167	45
Kidney beans, canned - 1 cup	74	230	32
Parmesan cheese - 1 tbsp	69	23	300
Green beans, cooked - 1 cup	58	44	132
Spinach, fresh chopped - 1 cup	55	12	542
Okra pods, fresh-cooked - 8	54	27	200
Orange, fresh medium - 1	52	60	87
Summer squash, cooked - 1 cup	48	36	133
Seaweed, kelp, raw - 1 oz	48	12	400
Looseleaf lettuce - 1 cup	38	10	380
Caulifower, cooked - 1 cup	34	30	113
Cabbage, raw shredded - 1 cup	32	16	200
Cantaloupe, melon - 1/8	29	94	31
Sirloin steak, lean - 8 oz	26	480	5
Whole wheat bread - 1 slice	20	70	31
Oatmeal, cooked - 1 cup	20	145	14
Peanuts, dried unsalted - 1 oz	17	161	11
Celery, outer stalk - 1	14	6	233
Sole/flounder, baked - 3 oz	13	120	11
Chicken breast, roassted - 1/2	13	142	9
Apple, fresh medium - 1	10	80	13

CORAL CALCIUM

There is a recent calcium supplement craze, feeding off osteoporosis fears. It is Coral Calcium, label-embellished with "mariine-grade, above-sea" and "superior to below-sea coral" with experts and proponents from both coral sea-levels flooding the cyberspace search engines.

Calcium is an essential mineral, and coral calcium (calcium carbonate) is one form of its many sources. To date, there has not been any studies proving superioriry of coral calcium to other forms of calcium supplements.

Two debunking website articles: "Coral Calcium debunked" and "Coral Calcium: The Joke's On You."

CALCIUM SUPPLEMENTS DIFFER IN BIOAVAILABILITY, SIMPLE ACID TEST SHOWS

Calcium supplements differ in bioavailability. The stomach absorbs some better than others. Dr. Michael Hollick, director of the Bone Healthcare Clinic at the Boston Medical Center, suggested a simple test to gauge the ability of the stomach for calcium supplement absorption. Mix the calcium preparation in white vinegar. In 20 minutes, if it hasn't dissolved in white vinegar, it's not likely to dissolve in your stomach either.

VEGANS DON'T NEED DAIRY FOR GOOD BONE HEALTH

Despite the vegan's dairy-free diet, they are in surprisingly good bone health. A study by Heather Hinkley, Ph.d and colleagues of the British College of Osteopathic Medicine in London, was done on 20-40 year-old women, followed for a minimum of 5 years, evaluated with broadband ultrasound attenuation of the calcaneum for bone mineral density assessment. There was no age-related decline in ultrasound attenuation among vegans. There was no statistical diffrerence between vegans and omnivores. The researchers speculate that a vegan diet may actually benefit bone health. 60% of vegans took calcium supplements which mave have contributed to the increased bone density. Also, the lack of dietary animal protein may be beneficial to the acid-base balance, with resulting less movement of bone mineral and decreased calcium excretion with preservation of bone integrity.

Sources

Calcium Supplements Differ in Bioavailability, Simple Acid Test Shows. Colin Nelson. Internal Med News. Aug 2005

Understanding Normal & Clinical Nutrition. Whitney, Cataldo, Rolfes. 2nd Ed. West Publishing Co. 1996

Cecil Textbook of Medicine. Wyngaarden and Smith. WB Saunders. 18th Ed.

Vegans Don't Need Dairy for Good Bone Health. Internal Medicine News. December 1, 2007

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