Triglycerides / HDL Ratio

Triglycerides are the fat your liver makes from surplus sugar and alcohol and sends into the blood in particles, and HDL is the particle that brings cholesterol back from the vessel wall. With a healthy sugar metabolism triglycerides are low and HDL is high. With belly fat and insulin resistance that tips: the liver makes more triglycerides, those particles swap fat with HDL on the way, and HDL becomes smaller and is broken down faster. Triglycerides go up and HDL goes down, in one movement, and the ratio between the two therefore rises on two sides at once. That makes the ratio a handy summary of the lipid pattern that goes with a deranged sugar metabolism, and that is also the lipid pattern that yields the small, dense LDL particles that lodge most easily in the vessel wall. A high ratio with a normal LDL is therefore a signal LDL alone does not show. The limitation is the same as with every division: the result does not say which of the two moved, and triglycerides move strongly with what you ate and drank in the hours before. Your report does not print the ratio; you calculate it with the calculator on this page, from triglycerides and HDL in mmol/L, and the result has no unit. The best-known cut-off, 2.27, comes from research in obese youths in American units and, converted to Dutch units, is about a 1. Anyone slim, who exercises and eats little sugar usually sits below 1; above 2 the lipid pattern of insulin resistance belongs with it.

The ratio is the value that shows whether your sugar metabolism is already working through into your lipid profile. Insulin resistance begins years before fasting glucose rises, and one of the first places it becomes visible is exactly this pair: triglycerides up, HDL down. Anyone with belly fat, who exercises little or eats a lot of sugar and fast carbohydrates sees the ratio rise while LDL and glucose are still normal. That is an early and cheap signal, from two numbers that sit in every lipid profile. The second reason is that the ratio shows the gain of lifestyle quickly. Triglycerides respond within weeks to less sugar, less alcohol and more exercise, and HDL follows over months; the ratio therefore falls earlier than LDL or HbA1c. Anyone working on their weight and their exercise has in this ratio a number that moves with what they do. The honest limitation is that the ratio appears on no Dutch report, that the Dutch risk estimate does not work with it, and that the only published cut-off comes from research in children in other units. The ratio is a summary and a trend, not a verdict. The direction, high triglycerides with low HDL, is the pattern described in type 2 diabetes, and that pattern counts.

A low ratio is favourable: triglycerides are low and HDL is high, the pattern of a healthy sugar metabolism. Drawing blood fasting instead of after a meal lets triglycerides fall and the ratio with them, so compare only measurements under the same conditions. Treating the underlying cause, losing weight, less alcohol, a diabetes coming under control, lets the ratio fall on two sides. A high HDL makes the denominator larger without anything changing about the triglycerides, and then a low ratio can hide triglycerides that are at the high end in themselves. A high ratio means triglycerides are high, HDL low, or both. Having eaten or drunk recently is the most common reason for an unexpectedly high result, because triglycerides rise after a meal and certainly after alcohol; repeat fasting. Belly fat and insulin resistance are the structural reason, and type 2 diabetes the end point of that, in which high triglycerides with a low HDL are the typical lipid pattern. Alcohol lifts triglycerides, even without a meal. Rare is oestrogen therapy, which raises triglycerides. A ratio above 2 with a normal LDL is a reason to look at glucose, insulin and your waist. Set the ratio beside the triglycerides and HDL themselves, because those are on your report and have a band, beside glucose, insulin and HbA1c, which show the sugar metabolism behind it, and beside non-HDL and ApoB, which the Dutch risk estimate works on.