Calcium Natural Sources
Of all the micro nutrients in our diet calcium is one of the big ones, requiring a whopping 1000mg per day. Although milk is often thought of the premium calcium source it is relatively low on these list of calcium rich foods. For calcium sources choose hard cheeses, seeds like sesame – tahini, chia, poppy, flax, nuts like almonds and brazil as well as dark leafy greens such as kale.
Daily Calcium Requirements
Infants 0-1 210-270mg
Children 1-3 yrs 500mg / 4-8yrs 800mg / 9-18yrs 1300mg
Calcium Rich Foods
Spices, poppy seed: 1438mg
Cheese, parmesan, hard: 1184mg
Cheese, romano: 1064mg
Cheese, gruyere: 1011mg
Cheese, goat, hard type: 895mg
Cheese, swiss: 791mg
Cheese, provolone: 756mg
Cheese, monterey: 746mg
Cheese, edam: 731mg
Cheese, cheddar: 721mg
Cheese, gouda: 700mg
Cheese, colby: 685mg
Seeds, chia seeds, dried: 631mg
Seaweed, agar, dried: 625mg
Cheese, blue: 528mg
Cheese, mozzarella, whole milk: 505mg
Cheese, limburger: 497mg
Cheese, feta: 493mg
Sardine, with bone: 382mg
Sesame seeds: 330mg
Carob, unsweetened: 303mg
Cheese, goat, semisoft type: 298mg
Almond butter: 270mg
Fish, anchovy, european, canned in oil, drained solids: 232mg
Fish, salmon, pink, canned, solids with bone and liquid: 213mg
Cheese, ricotta, whole milk: 207mg
Kale, scotch, raw: 205mg
LSA (miled linseed, sunflower seed and Almond): 202mg
Dandelion greens, raw: 187mg
Yoghurt, natural: 185mg
Cheese, brie: 184mg
Seaweed, kelp: 168mg
Fungi, Cloud ears, dried: 159mg
Seaweed, wakame, raw: 150mg
Taro, cooked: 149mg
Cocoa powder: 149mg
Bok choy: 123mg
Milk, regular fat: 98mg
Some calcium supplements are very hard to digest, while others are easier. Best forms – Calcium citrate, calcium citrate malate and calcium gluconate. Natural seaweed based calciums are also easily absorbed and used by the body.
Forms such as calcium orotate and carbonate are cheap, very hard to digest and should be avoided.
Also calcium carbonate from oyster shells or dolomite may be contaminated with heavy metals such as lead and aluminium.
Calcium hydroxyappetite is made from crushed bones and has been found to be more easily absorbed than carbonate and orotate.
Calcium absorption inhibited by:
Phytate: (phytic acid) inhibits calcium absorption.
Some fibres – bind to calcium and decrease absorption.
Oxalate – chelates calcium and increases fecal calcium excretion. Oxaltes are found in – spinach, rhubarb, swiss chard, celery, beets, eggplant, green okra, squash, blueberries, strawberries, blackberries, gooseberries, nuts – peanuts, pecans, tea, ovaltine, cocoa.
Magnesium, zinc and iron all compete with calcium for absorption.
Unabsorbed fatty acids in significant quantities in the gastrointestinal tract, form insoluble calcium soaps which cannot be absorbed and are therefore excreted in faeces.
Caffeine; produces small increases in urinary calcium excretion. It may also increase secretion of calcium into the GIT increasing fecal loss.
Alcohol; It is not known how, probably through increased urinary excretion due to increased urination.
Boron supplements greater than 3mg given with magnesium supplements greater than 200mg increase urinary calcium loss.
Age, due to decreased renal calcitriol production.
High plasma phosphorus concentrations may also decrease renal calcitriol production.
Estrogen deficiency at menopause decreases vitamin D mediated calcium absorption. This is why it is really important to make sure your calcium stores are high before menopause begins.
Calcium absorption improved by;
Vitamin D – stimulates absorption, in small intestine.
Fructose oligosaccharides, inulin and other non digestible saccharides enhance paracellular Calcium absorption.
Ingesting food or lactose (especially in infants and children) with calcium improves absorption.
Sugars, sugar alcohol (such as xylitol) and protein improve absorption.
Bacteria in the colon help to release calcium that is bound to some fermentable fibres such as pectins, releasing 4% to 10% of Calcium absorbed in a day.
The more you need the more you absorb, children absorb up to 75% of calcium ingested, whilst non lactating, non pregnant adults absorb only 30%.
Absorption increased with increases in parathyroid hormone.
It is estimated that 20% -50% of calcium from diet is absorbed, and 20%-35% form dairy products is absorbed (g). Absorption increases during pregnancy.