Causes of Calcium Deficiency

Calcium deficiency rarely has a single cause. It is usually a stack: too little coming in, too poorly absorbed, or too much being lost.

Too little coming in (dietary)

• Low dairy intake: milk, curd and paneer are the densest everyday sources; households that skip them start behind
• Cereal-dominated plates: wheat-and-rice meals with few greens, sesame, ragi or pulses mean chronically low intake
• Poverty and food habits: calcium-rich foods are often the first to go when budgets tighten
• Fad restriction: dairy-free or crash diets without planned substitutes

Poorly absorbed

• Vitamin D deficiency: the biggest single factor in India - without vitamin D, the gut absorbs only a fraction of dietary calcium
• Phytates and oxalates: unfermented whole grains, excess spinach and very high-bran diets bind calcium in the gut
• Gut diseases: celiac disease, inflammatory bowel disease, chronic diarrhea, bariatric surgery - all reduce absorption
• Advancing age: absorption efficiency falls after 60
• Certain medicines: long-term steroids, some anticonvulsants, and heavy proton-pump-inhibitor use

Too much lost or demanded

• Kidney disease: the kidneys regulate calcium and activate vitamin D; when they fail, both suffer
• High demands: pregnancy, breastfeeding, adolescent growth, and recovery from fractures
• Hormonal shifts: menopause drops estrogen, and bone loss accelerates sharply in the first post-menopausal years
• Excess caffeine, cola drinks, very high salt and smoking: each increases calcium loss or bone turnover modestly
• Parathyroid disorders: hypoparathyroidism lowers blood calcium directly (a medical cause, not dietary)

The classical cause list

Classical texts framed bone depletion (Asthi Kshaya) around depleting causes: dry, light and cold food; excessive pungent, bitter and astringent tastes; overexertion; fasting beyond capacity; suppression of natural urges; grief and worry; and aging itself - the vata-heavy pattern that dries and lightens the tissues (Charaka, Sutra Sthana 28; Sushruta, Sutra Sthana 15). They also name a failing tissue metabolism - weak asthi-dhatvagni - the classical way of saying the gut-bone supply line is broken. The overlap with the modern list (undernutrition, malabsorption, overexertion, aging, chronic illness) is direct.

One-line summary

Low intake plus low vitamin D is the everyday Indian combination; gut disease, kidney disease, steroids and menopause are the medical accelerators - and aging raises everyone's requirement.