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...