Introduction:

Nutritional assessment through biochemical methods, when compared with the other method of assessment i.e. anthropometric, clinical and dietary can potentially provide more meaningful and quotative data on one,s nutritional status. Biochemical test are an essential subset of clinical assessment and help to improve the health and well- being of patient.

biochemical method of Nutritional assessment

Biochemical biomarkers can often detect nutrient deficiencies before anthropometric measure are changed, or clinical sign and symptoms become visible.

Some of these tests are valuable indicator of recent dietary intake and are used in combination with dietary method to ascertain food and nutrient consumption. Biochemical testing improve the quality of diagnosis of specific diseases and reduce the chance of false decision made by the physicians

. These test are utilized validate different method of dietary assessment to determine whether the respondent are under or over - reporting . For example , to measure the proteins intake, food frequency form are used and to confirm them, 24-hours urine nitrogen secretion test can be performed.

Biochemical test of nutritional assessment can be grouped in to two arbitrary categories :Static test and functional tests, also referred as direct and indirect tests, respectively.

Importance of Biochemical Assessment:

Biochemical assessment plays an essential role in determining the nutrient status of individuals and communities. This helps in the early identification of nutritional deficiencies or excesses, which can contribute to various diseases. These tests also play a pivotal role in monitoring the effectiveness of nutritional interventions.

Commonly Used Biochemical Markers

Here are some of the commonly used biochemical markers in nutritional assessment:

Hemoglobin: Used to assess iron status and potential anemia.

Serum Albumin: Reflects protein-energy malnutrition.

Blood Glucose: Indicates carbohydrate metabolism and is a crucial marker for diabetes.

Serum Ferritin: Used to assess body's iron stores.

Vitamin D: Measured as 25-hydroxyvitamin D in serum to evaluate Vitamin D status.

Cholesterol and Triglycerides: Indicators of lipid metabolism and cardiovascular health.

Methodology:

Biochemical markers are measured from body fluids like blood or urine. Blood samples can be whole blood, plasma, or serum, while urine can be a 24-hour collection or random samples. The choice of specimen type depends on the nutrient or marker of interest. Various laboratory techniques are used for measurement, including but not limited to, spectrophotometry, immunoassays, mass spectrometry, and chromatography.

Limitations of Biochemical Assessment:

While biochemical assessments are highly valuable, they are not without limitations. Factors such as illness, medication, hydration status, and time of collection can influence results. Additionally, many nutrients do not have a specific or sensitive biochemical marker, making it challenging to assess their status.

Conclusion:

In conclusion, the biochemical method of nutritional assessment is a powerful tool for evaluating the nutritional status of an individual. It provides a more objective insight into the nutrient stores and metabolic processes in the body. However, it should be used in conjunction with dietary and anthropometric assessments for a more comprehensive understanding of an individual's nutritional status.

Static tests:

Static are classified as qualitative and quantitative biochemical markers. They are conducted to measure the nutrient metabolites in circulating blood, urine and body tissue , and identify the presence of nutritional deficiency or problem i.e. serum measurement of iron , retinol, vitamin B12 vitamin D , etc

Functional tests:

Functional tests are termed as biological, functional , and histologic indicator. These tests are conducted to assess physiological processes that rely on nutrient for their optimum performance, and generally, indicate the severity of deficiency .

For example, thiamine deficiency could be detected through urine sample, but transketolase enzyme in RBCs indicate the severity of deficiency. Beyond its vast utilization, there are some limitation associated with the biochemical tests.

Static tests might indicate the amount of certain nutrient with in blood, serum, or tissue but often fail to demonstrate the over all nutritional status of an individual .

They have also flailed to reflect the excess depletion of nutrients in human body. For example, calcium could be detected in serum, but this test alone is a poor indicator of over all calcium reserves of the body. Functional tests , despite their non-specificity, are an indicator of over all nutritional status

1)Protein

2)Water-soluble vitamins: folate, vitamin B6 and vitaminB12

3)Fat- soluble vitamin A and D

4)Minerals: iron, calcium, phosphorous, iodine, and other trace element

5)Level of blood lipid, glucose, various enzymes and metabolites implicated in metabolic syndrome and other chronic diseases.

What are method of nutritional status?
What are biochemical parameter?
What are the key biochemical markers used in the nutritional assessment of an individual?
How do factors such as illness, medication, and hydration status influence the results of biochemical methods of nutritional assessment?