B12 and Digestion
Absorption of B12 in the body:
As you can see below-- When you take an oral dose of Vitamin
B12, The first location for absorption by the body is in the stomach where
something called Intrinsic Factor (IF) is secreted to carry B12 to the small
intestine. Once B12 arrives in the terminal Ileum (end of small intestine), it
is transported by a protein called transcobalamin and then ready and available
for cell uptake.
Improper B12 absorption may result if digestion is
compromised for one reason or another such as:
1) Frequent use of Anti-Acids (Tums), Proton Pump Inhibitors
(Prilosec, Prevacid, Tagament, Pesid AC, Zantac, and certain medications like
Metformin.
2) Malabsorption: Leaky enterocytes in small intestine.
3) Celiac Disease
4) Inflammatory Bowel Disease (Crohn’s and Colitis)
5) Pernicious Anemia
6) Pancreatic Insufficiency
7) Alcoholism
B12 and the Diet
Our
dietary preferences can affect our intake of certain necessary vitamins
and minerals. The ONLY sources of B12 are found from animal sources. There are no vegetables with a high B12
content. Vegetarians and Vegans-be mindful of this!!
Table 2: Selected Food Sources of Vitamin B12 [13]
Food
|
Micrograms (mcg)
per serving |
Percent DV*
|
Clams, cooked, 3 ounces
|
84.1
|
1,402
|
Liver, beef, cooked, 3 ounces
|
70.7
|
1,178
|
Breakfast cereals, fortified with 100% of the
DV for vitamin B12, 1 serving
|
6.0
|
100
|
Trout, rainbow, wild, cooked, 3 ounces
|
5.4
|
90
|
Salmon, sockeye, cooked, 3 ounces
|
4.8
|
80
|
Trout, rainbow, farmed, cooked, 3 ounces
|
3.5
|
58
|
Tuna fish, light, canned in water, 3 ounces
|
2.5
|
42
|
Cheeseburger, double patty and bun, 1
sandwich
|
2.1
|
35
|
Haddock, cooked, 3 ounces
|
1.8
|
30
|
Breakfast cereals, fortified with 25% of the
DV for vitamin B12, 1 serving
|
1.5
|
25
|
Beef, top sirloin, broiled, 3 ounces
|
1.4
|
23
|
Milk, low-fat, 1 cup
|
1.2
|
18
|
Yogurt, fruit, low-fat, 8 ounces
|
1.1
|
18
|
Cheese, Swiss, 1 ounce
|
0.9
|
15
|
Beef taco, 1 soft taco
|
0.9
|
15
|
Ham, cured, roasted, 3 ounces
|
0.6
|
10
|
Egg, whole, hard boiled, 1 large
|
0.6
|
10
|
Chicken, breast meat, roasted, 3 ounces
|
0.3
|
5
|
*DV = Daily Value. DVs were developed by the
U.S. Food and Drug Administration (FDA) to help consumers determine the level
of various nutrients in a standard serving of food in relation to their
approximate requirement for it. The DV for vitamin B12 is 6.0 mcg. However, the
FDA does not require food labels to list vitamin B12 content unless a food has
been fortified with this nutrient. Foods providing 20% or more of the DV are
considered to be high sources of a nutrient, but foods providing lower
percentages of the DV also contribute to a healthful diet. The U.S. Department
of Agriculture's Nutrient
Database Web site [13]) lists the nutrient content of many foods
and provides acomprehensive list of foods containing vitamin B12.
B12 and Depression
Inadequate intake, digestion, or assimilation of B12 can affect our mental/emotional health. In an Observational study, it was found that 30% of hospitalized, depressive patients were found to have a B12 deficiency. B12 plays a role in the production of SAMe which is responsible for the bioavailability of neurotransmitters causative of depression. Those struggling with depression should be screened for B12 levels as a standard measure.
Signs and Symptoms of B12 deficiency:
· Fatigue
· Megaloblastic
Anemia
· Constipation
· Loss
of appetite
· Weight
Loss
· Neurological
Changes (numbness and tingling in hands and feet)
· Difficulty
maintaining balance
· Confusion
· Poor
memory
· Depression
· Soreness
of mouth or tongue
· Swelling
of tongue
And there is much more that B12 does, and many more conditions that it will benefit. Stay tuned for more....
