Essay about To Eat or Not to Eat
To eat or not to eat? That is the question. “I have made an appointment to have my blood lipid levels checked, but I can’t remember if my doctor mentioned fasting before the blood test. And I’ve heard that it is unnecessary to fast before a blood test. Is this true? ” Nowadays, people are more concerned and aware of how much fat is in their diet. Having your blood lipid levels tested regularly is a good way to keep track of this. However, it is often inconvenient for many people to fast before a blood test as the idea of missing a meal can be disconcerting.
A recent study, done by students of HUNT221 at the University of Otago, looks into the effect of blood lipid levels after consuming different types of meals, compared with fasting. In the experiment, total (plasma) cholesterol and triacylglycerol (1) concentrations were monitored between fasting and non-fasting blood tests. The aim of the investigation was to identify whether these lipid levels were raised by recently ingested meals. Subjects were required to consume a high carbohydrate (CHO) or high fat meal with similar energy and protein content.
The results obtained were necessary to determine if there was a post-prandial(2) effect on the true validity of the lipid concentrations. This is also useful for diagnosing blood lipid disorders such as high cholesterol. All subjects were required to provide a fasting blood sample to show a baseline for the lipid concentration. The fasting results showed a mean total cholestrol level of 4. 36 mmol/L and a mean triacylglyceride level of 1. 13 mmol/L. The study showed that the lipid concentrations between subjects who ingested a high carbohydrate meal and those fasting were similar.
There were no significant value to show that the high carbohydrate meal had an effect on lipid levels in the blood. Triglyeride levels in CHOs are generally low(? ), explaining the little effect that a high CHO meal has on triglyercide levels in the blood. However not all foods high in CHO are low in triglycerides. For example, muffins which are considered to be high in CHO also have an elevated amount of hidden fat. So yes, that toast with your favourite low-fat spread is okay to have before going for your blood test. But always check with your GP first.
When comparing the high fat and the fasting blood samples, it showed that there was a significant increase of 20% in total blood triacylglyceride concentrations. The total cholesterol concentration did not change significantly. This suggesting that by eating a high fat meal, the triacylglyceride levels will be affected; hence the blood test would not be accurate and would not provide a correct indication of actual lipid levels. Therefore, lipid intake should be kept to a minimum before a blood test. . Replacing standard dairy products for low-fat alternatives is better when considering eating before a blood test (3).
Also look out for hidden lipids in foods high in carbohydrates by checking nutrition panels on the packaging. So to answer your question, it is preferable to fast for 10 to 12 hours to avoid obtaining invalid results. However, if it is necessary to eat, avoid high fat foods such as bacon and eggs, or high fat spreads. Rather, you can opt for carbohydrate foods such as fruits and vegetables or breads and cereals. It is necessary however to keep in mind that these suggestions only apply when testing for blood lipids levels, if in doubt talk to your GP.