Many researchers have a difficult time defining exactly what malnutrition is. Some like to believe that it is a deficiency in caloric intake whereas others believe it is a deficiency in protein or vitamin intake or perhaps some combination thereof. When measuring the overall nutritional health of a person in a hospital setting, the most common test administered assesses the concentration of transport proteins in the blood. Low concentrations of transport proteins are typically associated with inflammation of the intestines that occur during hunger and malnutrition. On the other hand, concentrations that are too high can signal other health hazards such as dehydration and hormonal imbalances.
Albumin
Of all proteins that make up human plasma, albumin is the most prevalent. Albumin testing was one of the first well-established quantitative measurements used to assess a person’s malnutrition. The protein is synthesized in the liver and accounts for just over half of all serum protein in the bloodstream and organs. One major issue with albumin testing is that changes in albumin levels can occur due to many other external factors other than malnutrition. In order for one to be reasonably certain that a change in albumin levels is due to malnutrition, multiple samples are needed over a timeframe of at least three weeks.
Prealbumin
Prealbumin, which is now more commonly referred to as Transthyretin (TTR) has recently been getting larger attention from gastroenterologists and nutritional health researchers as an alternative to the traditional albumin testing. Since prealbumin has a much shorter half-life, the proteins themselves are typically broken down more quickly than other serum proteins. Because they must be replenished more often, they are often a good indicator of whether or not a person has gotten adequate nutrition recently. They are also more resistant to external factors then albumin and therefore require fewer samples over a shorter time frame in order to achieve a statistically significant result. In fact, most prealbumin tests can take as little as 1 to 2 days to determine nutritional status.
Conclusion
While the two serums are both good measures of a person’s overall nutritional health with respect to protein levels, albumin is more often used to indicate the long-term health whereas prealbumin is better for accurately measuring recent dietary intake. Either protein can be administered intravenously to patients who are lacking them and unable to synthesize them independently due to various health reasons. There are also several other different types of serum proteins, many of which are currently being tested to see if they can provide more accurate bio-statistical evidence of malnutrition.
