Minerals and Bone Health Flashcards
1
Q
What are Minerals?
A
- Major mineral- you need more than 100mg/d
- Trace elements - you need less than 100 mg/d
2
Q
What do Minerals do?
A
- Structural Roles
- Calcium, magnesium, phosphorus and fluoride are needed for the structure of bone
- Regulatory roles:
- Iodine is used to make thyroid hormones - metabolic rate
3
Q
Bone Consists of…
A
- 65% minerals -> Hardness
- 35% organic substances -> strength and flexibility
4
Q
Calcium is
A
- A major mineral - we need > 100mg
- It makes up 2% of our body weight
5
Q
Sources of Calcium
A
- Tofu
- Some nuts (almonds) and seeds (sesame)
6
Q
Absorption of Calcium
A
- Only about 25% of the calcium in foods is absorbed
- Less if you have a diet low in Vitamin D
- Pregnant women need much more calcium and so the body adapts to absorb more
7
Q
Getting the Most Out of your Calcium
A
- Your intestine only absorb about 1 cup of milk’s worth at one time
- Oxylates (spinach), Phytates (whole grains) and tannins )tea) decrease absorption
- Avoid taking zinc, iron or magnesium supplements when you’re eating a source of calcium
8
Q
Note for Dairy-Free Folks
A
- High calcium leafy greens
- Tofu
9
Q
Calcium is Critical for Strong Bones
A
- 99% calcium stored in bones
- Critical part of hydroxyapatite crystals
- Oxygen and hydrogen in the middle
10
Q
Calcium has another role as an Electrolyte
A
- 1% calcium is in the blood as an electrolyte:
- Regulate heart beat
- Muscle contraction and relaxation
- In muscle contraction the nerves tell the muscle to contract and the calcium moves into the muscles
11
Q
If you’re not Getting Enough Calcium
A
- Your body will take what it needs from your bones
- Blood Ca levels don’t change but bones weaken
12
Q
What if I cant get Enough?
A
- Amount - you cant absorb more than ~500mg
- Most supplements are about 30% absorbed
- Calcium carbonate is the cheapest: TUMS
13
Q
Maximizing Supplement Absorption
A
- Don’t take calcium with a multivitamin
- Take a calcium supplement with food:
- Its absorbed better
14
Q
What if I eat too much Calcium?
A
- Eating more doesn’t change blood level of calcium
- The extra comes out in the feces
- Particularly iron and zinc
- Different cultures have different rules in relation to nutrition
- Jewish: don’t eat meat and milk together, started religiously but later realized it had health benefits
15
Q
Phosphorus
A
- Another major mineral (>100mg/d needed)
- 85% phosphorus is found in bones
