Download Vitamin B6 - Medical Nutrition Therapy Manual

Beretich, Kaitlan. Vitamin B6. KNH 413 – Medical Nutrition Therapy II. Miami University, Oxford,
Ohio, Spring 2013.
Vitamin B6
1. What is the nutrient?
 Vitamin B6
 Also know as pyridoxine
 Water soluble vitamin
 Dissolve in water
 Body cannot store them
 Leftover amounts of the vitamin leave body through the urine
 Need a continuous supply of B6 in the diet
 Makes antibodies which are needed to fight many diseases
 Maintain normal nerve function
 Make hemoglobin which carries oxygen in the red blood cells to the tissues
 A vitamin B6 deficiency can cause a form of anemia
 Break down proteins
 Keep blood sugar in normal ranges
 (MedlinePlus & Mayo Clinic)
2. What is the RDA/DRI for the nutrient?
 Adequate Intake
 Infants 0 - 6 months: 0.1 mg
 Infants 7 months – 1 year: 0.3 mg
 RDA
 Children 1 – 3 years: 0.5 mg
 Children 4 – 8 years: 0.6 mg
 Children 9 -13 years: 1 mg
 Children 14 – 18 years: 1.3 mg
 Children 14 – 18 years: 1.2 mg
 Adults 19 – 50 years: 1.3 mg
 Men 51 years and older: 1.7 mg
 Women 51 years and older: 1.5 mg
 Pregnant women: 1.9 mg
 Breastfeeding women: 2.0 mg
 (University of Maryland Medical Center)
3. How is the nutrient metabolized?
 All B vitamins help the body convert food (carbohydrates) into fuel (glucose)
 All B vitamins are water-soluble, meaning that the body does not store them
 B complex vitamins also help metabolize fats and protein
 B6 is readily absorbed in the small intestine
 The forms of vitamin B6 found in food are converted to active forms in the liver
 Vitamin B6 helps the body make several neurotransmitters
 Chemicals that carry signals from one nerve cell to another



 Serotonin and norepinephrine
Helps control levels of homocysteine in the blood
Body needs vitamin B6 in order to absorb vitamin B12 and to make red blood cells
and cells of the immune system
(University of Maryland Medical Center)
4. What are food sources of the nutrient?
 Chicken
 Turkey
 Tuna
 Salmon
 Shrimp
 Beef liver
 Milk
 Cheese
 Lentils
 Beans
 Spinach
 Carrots
 Brown rice
 Bran
 Sunflower seeds
 Wheat germ
 Whole-grain flour
 (University of Maryland Medical Center)
5. What disease states alter the nutrients metabolism?
 Alcoholism
 Increased destruction and reduced formation of vitamin B6
 Cirrhosis
 Due to the loss of liver function, vitamin B6 cannot be converted to its
active form from foods
 Chronic Kidney Disease Stage Five
 Cofactors involved in homocysteine metabolism, including vitamin B6 are
less available due to dialysis losses and overall decreased dietary intake
due to dietary restrictions
 People with autoimmune disorders
 Rheumatoid arthritis
 Celiac disease
 Crohn’s disease
 Ulcerative colitis inflammatory bowel disease
 (Nutrition Therapy & Pathophysiology & National Institues of Health)
6. What are the tests or procedures to assess the nutrient level in the body?
 While a vitamin B6 deficiency is uncommon in the U.S., a simple blood test can
be administered to determine B6 levels in the body.

(National Institues of Health)
7. What are the drug–nutrient interactions?
 Drugs that reduce levels of B6 in the body
 Cycloserine (Seromycin): used to treat tuberculosis
 Hydralazine (Apresoline): used to treat high blood pressure
 Isoniazid: used to treat tuberculosis
 Penicillamine: used to treat rheumatoid arthritis
 Theophylline (TheoDur): used to treat asthma
 Antibiotics, Tetracycline
 All B complex vitamins, including vitamin B6, interfere with the
absorption and effectiveness of antibiotic tetracycline. You should take
tetracycline at different times from vitamin B6 and other B vitamins.
 Antidepressant Medications
 Taking vitamin B6 supplements may improve the effectiveness of some
tricyclic antidepressants such as nortriptyline (Pamelor), especially in
elderly people. Other tricyclic antidepressants include amitriptyline
(Elavil), desipramine (Norpramin), and imipramine (Tofranil). On the
other hand, antidepressants called monoamine oxidase inhibitors
(MAOIs) may reduce blood levels of vitamin B6. Examples of MAOIs
include phenelzine (Nardil) and tranylcypromine (Parnate).
 Amiodarone (Cordarone)
 This drug, used to treat an irregular heartbeat, makes your skin more
sensitive to sunlight. Taking vitamin B6 along with this drug may increase
your risk of sunburn, blistering, or a rash.
 Chemotherapy drugs
 Vitamin B6 may reduce certain side effects of 5-fluorouracil and
doxorubicin, medications used to treat cancer. Talk to your doctor before
taking any supplement if you are undergoing chemotherapy.
 Erythropoietin (EPO)
 Erythropoietin therapy, used to treat severe anemia, may decrease
vitamin B6 levels in red blood cells.
 Levodopa (L-dopa)
 Vitamin B6 reduces the effectiveness of levodopa, a medication used to
treat Parkinson's disease. However, it does not seem to have the same
effect on the combination of levodopa and carbidopa. Your doctor may
be able to determine a dose of B6 that can safely help reduce side effects
of levodopa. Taking vitamin B6 along with levodopa should be done only
under your doctor’s supervision.
 Phenytoin (Dilantin)
 Vitamin B6 makes phenytoin, a medication used to treat seizures, less
effective.
 (University of Maryland Medical Center)
8. How is the nutrient measured?
 Vitamin B6 is measured in milligrams per day (mg/day)
 (Nutrition Therapy & Pathophysiology)
9. What are the Upper Tolerable Limits?
 UL
 Infants 0 – 6 months: No data
 Infants 7 – 12 months: No data
 Children 1 – 3 years: 30 mg/d
 Children 4 – 8 years: 40 mg/d
 Males, Females 9 – 13 years: 60 mg/d
 Males, Females 14 – 18 years: 80 mg/d
 Males, Females 19 – 70 years: 100 mg/d
 Males, Females > 70 years: 100 mg/d
 Pregnancy ≤ 18 years: 80 mg/d
 Pregnancy 19 – 50 years: 100 mg/d
 (Nutrition: An Applied Approach)
10. What are the physical signs of deficiency?
 Confusion
 Depression
 Irritability
 Mouth and tongue sores
 (MedlinePlus)
11. What are physical signs of toxicity?
 Difficulty coordinating movement
 Numbness
 Sensory changes
 (MedlinePlus)