25 October 2008

Vitamin E

Alpha tocopherol is a type of vitamin E that exists naturally as d-alpha tocopherol, but supplement manufacturers also market synthetic "mirror image" l-alpha tocopherol as well as a mixture of d- and l-alpha tocopherol.

The synthetic kind and the mix are cheaper, but l-alpha tocopherol has little or no actual vitamin E activity in the body. It may interfere with d-alpha tocopherol activity and there's no long-term safety data.

When buying vitamin E supplements, be sure to choose d-alpha tocopherol along with other natural tocopherols such as beta-, gamma- and delta-.

Reference

1. Gaby, A. Does high-dose vitamin E kill people? Townsend Letter for Doctors and Patients. Available at: http://findarticles.com/p/articles/mi_m0ISW/is_259-260/ai_n10299312/pg_2. Accessed on Oct. 25, 2008.

18 October 2008

Walk for your memory

You may or may not remember last year's landmark four-year study related to Alzheimer's disease sponsored by the Italians. The study appeared in December's issue of Neurology. I found a link to an article about it below.

In summary it showed that elderly people (over 65) who regularly walk significantly lower risk of vascular dementia.(1) Thus there is a lot of talk about physical activity, like walking, as having a potential effect for reducing risk of Alzheimer's disease.(1) Because walking and other activity increases oxygen in the brain, it may be directly improve memory.(1)

Suggestion: Walk a mile or two before taking Anatomy and Physiology tests!

Reference

1. American Academy of Neurology. Walking and moderate exercise help prevent dementia. ScienceDaily. Available at: http://www.sciencedaily.com/releases/2007/12/071219202948.htm. Accessed on Oct. 18, 2008.

"It's not a tumor"

Many of us will remember the scene in Kindergarten Cop when detective John Kimble (Arnold Schwarznegger) said he had a headache.

"It might be a tumor," said Lowell, one of the kids.

"It's not a tumor!" said John.

Actually it may have been a tumor, or more correctly a brain tumor, since one of the symptoms is a headache.(1) Other symptoms would be poor balance and coordination, dizziness, double vision, slurred speech (still Arnold?), nausea and vomiting, fever, abnormal pulse, breathing rates, personality changes, numbness and weakness of the limbs (definitely not Arnold), and seizures.(1p518)

What is a brain tumor?

A brain tumor is an abnormal growth of tissue in the brain that could be malignant or benign, which are both equally serious because the tumor compresses adjacent tissues and causes a build-up of pressure in the skull.(1p518)

Treatment

Treatment for brain turmors, which can include surgery, radiation therapy and/or chemotherapy, can vary depending on size, location and type of the brain tumor.(1p518)

Reference

1. Tortora, GJ & Derrickson, B. Principles of Anatomy and Physiology, 11th ed; 2006. New York: John Wiley & Sons.

ADHD and omega-3

According to an article in the Scandinavian Journal of Nutrition (Scandinavia being where much of our purified fish oil supplements comes from), there is "mounting evidence" showing that fish oil DHA/EPA omega-3 fatty acids can be used in clinical treatment of ADHD.(1)

Several studies have reported that supplementation with fish oil at high dosages (16g per day - that's really high) was shown to provide significant results in behavioral patterns.(2)

References

1. Richardson, A.J. The importance of omega-3 fatty acids for behaviour, cognition and mood. Available at: http://www.ingentaconnect.com/content/tandf/ssnu/2003/00000047/00000002/art00008. Accessed on Oct. 18, 2008.

2. Sorgi, P.J., Hallowell, E.M., Hutchins, H.L, & Sears, B. "Effects of an open-label pilot study with high-dose EPA/DHA concentrates on plasma phospholipids and behavior in children with attention deficit hyperactivity disorder." Journal of Developmental & Behavioural Pediatrics; 2007, 28:82-91.

Take Tylenol not Aspirin (unless you have osteoporosis, in which take fish oil and glucosamine)

Aspirin (acetylsalicylic acid) is a carboxylic acid derivative while Tylenol (acetaminophen) is an amide derivative.(1p478, 506) Both act as analgesics for relieving pain and reducing fever.

By inhibiting the enzyme cyclooxygenase in prostaglandin synthesis, aspirin reduces inflammation making it a nonsteroidal anti-inflammatory drug.(1p478) In the stomach environment, the carboxylic acid derivative reacts directly with the stomach lining and can potentially cause bleeding.(2 & 3)

Tylenol acts on nerve endings to suppress pain, but is not a nonsteroidal anti-inflammatory drug.(3 & 1p506) In the stomach environment, because of its structure as an amide derivative, it doesn't react with the stomach lining and causes no bleeding.(2)

References

1. Denniston, KJ, Topping, JJ & Caret, RL. General, Organic, And Biochemistry, 5th ed. New York: McGraw Hill; 2007.
2. Kleiner, K. Fatty molecules make aspirin easier to stomach. Available at: http://www.newscientist.com/article/mg14519652.700-fatty-molecules-make-aspirin-easier-to-stomach.html. Accessed on Oct. 18, 2008.
3. Papazian, R. OTC options: Pain pain go away. FDA Consumer. Available at: http://www.fda.gov/bbs/topics/CONSUMER/CON00296a.html. Accessed on Oct. 18, 2008.

Why do pregnant women need iron?

Pregnant women need additional iron intake, but if the body controls absorption and uptake, then why is diet not enough? While it may be true that the diet doesn't provide enough, it may also include other factors beyond iron intake that may also affect women pre- and post-pregnancy.

There are many dietary factors that can inhibit iron absorption.(1) Among these factors are:

- polyphenols of gallic acid that are found in coffee and tea,
- oxalic acid of spinach, chard, berries, chocolate and tea,
- phytates found in legumes,
- preservatives like EDTA,
- phosvitin found in egg yolks;
- and other minerals such as calcium, calcium phosphate salts, zinc, manganese, and nickel.(1p422)

In addition, there are factors that enhance iron absorption. These include:

- acids like ascorbic, citric, lactic and tartaric acid
- sugars
- meat, poultry and fish
- and mucin.(1p422)

When iron deficiency is a problem, thus, wisdom would suggest considering what is inhibiting absorption and what could be added to the diet to enhance absorption.

Reference

1. Gropper, S.S., Smith, J.L. & Groff, J.L. Advanced Nutrition and Human Metabolism, 4th ed; 2005. Belmont, CA: Thomson Wadsworth.

Sodium supplements or salt shakers?

I couldn't imagine why anyone would supplement with sodium. We do so much "supplementation" already with our salt shakers. All that shaking is linked to hypertension, but overall, when food is salted lightly, the salting may not be all bad.

When you eat salt, it guards you against sodium deficiency. The deficiency is not as likely now, but in earlier days it may have been an issue and continues to be a problem with anorexia.(1) The deficiency's symptoms include nausea, muscle atrophy, poor growth and weight loss.(1p380)

Plus, if the salt is iodized, then it helps guard against iodine deficiency. Iodine is extremely variable in foods so having it as part of salt is beneficial.(1p468) The thyroid collects the iodine, in its ionic form iodide, and uses it for genesis of hormones.(1p418)

Reference

1. Gropper, S.S., Smith, J.L. & Groff, J.L. Advanced Nutrition and Human Metabolism, 4th ed; 2005. Belmont, CA: Thomson Wadsworth.

10 October 2008

Vitamin Supplementation Debate

Vitamin supplementation may have its place in clinical nutrition, but confusion of how or when to supplement can ultimately harm the consumer.(1) The confusion arises from "extreme" views of healthcare practitioners who say supplementation is not necessary at all and those who push for too much supplementation.(1p119) Non-credentialed experts and vitamins manufacturers interested in making profits may also lead consumers in the wrong paths.(1p119)

Pros of Supplementation

As a person ages or changes his or her diet or environment, vitamin needs can change resulting in a potential need for help from vitamin supplementation.(1p119)

Supplementation can remove the guesswork out of making sure enough of a certain vitamin is in the diet. A woman, for example, who has a need for additional folic acid during times of pregnancy may choose supplementation rather than attempting to make significant changes to diet.(1p119) A child or adolescent can also be given supplements to be sure of healthy growth despite a reluctance to eat a balanced diet.(1p119)

Supplementation can be used to prevent clinical issues.(1p119) An example includes infants given vitamin K and D and trace minerals iron and fluoride.(p119)

Impaired nutrient absorption, storage and usage can be helped by supplementation.(1p119) An example includes elderly who may may need vitamin C, thiamin, riboflavin, pyridoxine and cobalamin.(1p119)

Lifestyle choices may influence need of supplementation.(1p120) Use of oral contraceptives, restricted diets, exercise programs, smoking, alcohol and caffeine can all generate situations of vitamin deficiency due to insufficient dietary intake and/or interference with absorption of vitamins.(1p120)

Certain diseases may create a situation where a person could benefit from supplementation.(1p120) Especially in cases of long-term illness, supplementation can be used to meet increased vitamin needs to support the body.(1p120)

Cons of Supplementation

While there are many "pros" to vitamin supplementation, the "cons" can be equal in detriment. A large amount of a certain vitamin can be toxic such as the case of retinol, which has potential of causing liver or brain damage.(1p120)

Megadoses of vitamins can also lead to a deficiency of another vitamin due to how they work together in the body.(1p120) An "artificially induced" deficiency can result when a person suddenly stops taking a large amount of a certain vitamin, such as infants who develop scurvy because their mothers took megadoses of vitamin C during pregnancy.(1p121)

A non-credentialed "expert" or vitamin manufacturer may miss these points as he or she recommends or markets certain vitamins to unsuspecting customers.

Conclusion

Proper vitamin supplementation should be done with wisdom and care. Supplementation principles include reading labels carefully, understanding that large doses can be harmful, that supplement use is governed by individual needs, that all nutrients work together, and that food remains the best source of nutrients.(1p121) Lastly, sound knowledge and evidence should guide reasons for supplementation.(1p121)

Reference

1. Nix, S. Williams' Basic Nutrition &Diet Therapy, 12th ed, Elsvier Mosby, 2001; 119-121.

04 October 2008

Health Starts in The Gut

Going in with the gut, I'm led to deduce that health begins exactly there.

The gut and other parts of the gastrointestinal system make up the basic conduit of nutrition.(1) Food eaten is broken down by the system into simpler substances, nutrients are absorbed and transported to cells, and then are metabolized for creation of new body substances or for energy. (1p58)

Clinical Applications of Digestion, Metabolism and Absorption

Clinical application begins with the knowledge of how the process of digestion works. A nutritionist can then begin applying solutions.(1p67) To help a patient limit burping, a nutritionist can suggest he or she avoid nervously gulping down carbonated beverages through a straw.(1p67) To limit flatulence in a patient, the nutritionist can recommend he or she limit fiber and slowly reintroduce it in the diet or take a lactase supplement before consuming milk.(1p67)

Nutritionists can use diet therapy to also encourage absorption and metabolism of nutrients. An example is inclusion of non-digestible oligosaccharides to the diet. Understanding how these nutrients affect growth of intestinal flora helps a nutritionist encourage proper mineral absorption such as calcium in a patient.(2, 3, 4)

Clinical Applications of Energy Balance

Energy balance is a chief factor when nutritionists consider diet therapy. The food the body digests is partly converted to energy through cell metabolism.(1p74) Nutritionists should know how foods affect energy via each kilocalorie present.(1p75) For proper health, the body must have a sufficient amount of kilocalories from food for fuel and function, but not so much daily that would lead to gain of too much weight.(1p75, 81)

The amount of kilocalories for proper energy balance requires evaluation of daily energy requirements. Nutritionists would consider the body’s uses of energy, namely resting metabolic rate, physical activity and thermic effect of food.(1p81) A calculation of total energy output can then determine how many calories a patient should receive.(1p81)

Basing clinical diet therapy on energy balance as well as digestion, absorption and metabolism, the patient is adequately served and sure to receive best results.

References

1. Nix, Staci, Williams' Basic Nutrition &Diet Therapy, 12th edition, Elsvier Mosby, 2001; 57-86.

2. Kolida, S & Gibson. Prebiotic capacity of inulin-type fructans. In: Inulin and oligofructose: Health benefits and claims-A critical review. J of Nutrition. November 2007; 137 (suppl):11S.

3. Scholz-Ahrens, KE & Schrezenmeir, J. Inulin and oligofructose and mineral metabolism: The evidence from animal trials. In: Inulin and oligofructose: Health benefits and claims-A critical review. J of Nutrition. November 2007; 137 (suppl):11S.

4. Abrams, SA, Griffin, J, and Hawthorne, KM. Young adolescents who respond to an inulin-type fructan substantially increase total absorbed calcium and daily calcium accretion to the skeleton. In: Inulin and oligofructose: Health benefits and claims-A critical review. J of Nutrition. November 2007; 137 (suppl):11S.

Women and Asians can't hold their alcohol as well as European men

If you thought it interesting that women have less of aldehyde dehydrogenase, then you'll no doubt be interested to know that many Asians have a deficiency.(1) This is why Chinese, Japanese and Koreans can be much more sensitive to alcohol than Europeans and Americans of European ancestry.(1) You'll notice that Asians with this deficiency are susceptible to alcohol-induced flushing.(1)

The adaptation that those of European ancestry have to be able to handle alcohol may be due differences of water intake in the continents, according to Sharon Moalem, Ph.D.(2) To reduce disease by avoiding pathogens in the water, early Asians boiled water for drinking tea.(2) Early Europeans, however, may have used fermentation so the alcohol would kill the pathogens.(2)

1. Wall, TL, Peterson, CM, Peterson, KP, Johnson, ML, Thomasson, HR, et al. Alcohol Metabolism in Asian-American Men with Genetic Polymorphisms of Aldehyde Dehydrogenase. Annals of Internal Medicine; September 2007:127(5)376-379. Available at http://www.annals.org/cgi/content/full/127/5/376. Accessed on October 4, 2008.

2. Moalem, S. Survival of the Sickest: The Surprising Connections Between Disease and Longevity; 2006. New York: HarperCollins.

Want a reason to get drunk?

An incredibly risky one? If you happen to drink methanol, then you'll end up in the emergency room with an IV intended to get you drunk as fast as possible.1 2 If the treatment isn't applied immediately you could end up blind or worse.1,2p426

Methanol may be good for certain racing cars, but it's toxic to human beings because the body's liver oxidizes it to produce formaldehyde.2p387,426 This particular aldehyde is highly reactive in the body, damaging cells and their vital proteins including DNA.2p426,4 Even the fumes of formaldehyde may be cancerous.1,3 Formaldehyde in the body will lead to loss of eyesight, respiratory failure, convulsions and death.2p426

To keep the liver from oxidizing methanol to formaldehyde, the ER personnel will use ethanol as a distraction.2p426 Ethanol, the by-product of yeast found in alcoholic drinks, is oxidized by the liver using the same enzyme that oxidizes methanol.2p387,426 In fact, it is preferred by the enzyme, which helps minimize production of formaldehyde through "competitive inhibition".2p426

The product of ethanol oxidation is acetaldehyde, which is less toxic.2p426 Acetaldehyde will give a person a hangover in the morning and too much over time can lead to fatty liver disease, but its effects are nowhere near those of formaldehyde.2p430 The liver detoxifies acetaldehyde to etanoic acid and then used as an caloric energy source.2p430

1. Antizol. Methanol poisoning overview. Available at: http://www.antizol.com/mpoisono.htm. Accessed on September 30, 2008.

2. Denniston, KJ, Topping, JJ & Caret, RL. General, Organic, And Biochemistry, 5th ed. New York: McGraw Hill; 2007:426.

3. National Cancer Institute. Formaldehyde and cancer: Questions and answers. Available at: http://www.cancer.gov/cancertopics/factsheet/risk/formaldehyde. Accessed on September 30, 2008.

4. Salariino, AJ, Wiley, JC, Lechner, JF, Grafstrom, RC, LaVeck, M & Harris, CC. Effects of Formaldehyde, Acetaldehyde, Benzoyl Peroxide, and Hydrogen Peroxide on Cultured Normal Human Bronchial Epithelial Cells. Cancer Research, vol 45; 1985 June. Available at: http://cancerres.aacrjournals.org/cgi/reprint/45/6/2522?ck=nck. Accessed on September 30,2008.