Cholesterol: H for healthy, L for lousy
Your level of cholesterol has to be viewed as part of your overall cardiovascular health risk
Cholesterol testing: A high HDL is protective because HDL carries cholesterol away from the arteries and back to the liver, protecting against its accumulation on artery walls. A low HDL can put you at risk of heart disease. Photograph: Getty Images
Occasionally I see people who are upset, even distressed, about an elevated cholesterol test result. Interpreting the results can be difficult, particularly when consultation times with doctors are tight and there are other health issues to discuss.
Blood lipids, especially the different cholesterol types and triglyceride levels, can be confusing. Remembering which type (HDL or LDL) is the healthy cholesterol can be hard to recall, quite apart from the implications of a result outside the normal range.
Your level of cholesterol or triglycerides has to be viewed as part of your overall cardiovascular health risk.
Your risk of having a heart event can vary considerably, depending on what fraction of cholesterol is pushing up the total cholesterol. A high HDL (think of H for healthy) is protective because HDL carries cholesterol away from the arteries and back to the liver, protecting against its accumulation on artery walls. A low HDL can put you at risk of heart disease.
There is good evidence to demonstrate that stress can actually increase your LDL cholesterol (think of L for lousy) so worrying unnecessarily about an elevated cholesterol result, in the absence of other risk factors, is not a great strategy.
Talk to your GP about your overall risk of disease and look at your result in this context.
The cholesterol table on this page shows levels generally regarded as desirable.
If, on the other hand, the number of risk factors is accumulating over time, it may be worth reflecting on this.
Despite the fact that your medication may be controlling your blood cholesterol and blood pressure, further and fundamental changes to your lifestyle may alter your risk of disease.
Metabolic syndrome is a cluster of risk factors that, together
, may be related to insulin resistance and an increased risk of heart disease and type 2 diabetes.
Individuals with metabolic syndrome are more disposed to other conditions such as polycystic ovary syndrome, non-alcoholic fatty liver disease and certain types of cancer.
Having any three or more of the following risk factors signifies a diagnosis of metabolic syndrome in adults (adapted from the American Heart Association definition):
nAn increased waist circumference. This is
greater than or equal to 94 cm and greater than or equal to 80cm for Caucasian men and women respectively.
nA raised triglyceride level, greater than 1·7 mmol/L (or if you are already on treatment to lower triglycerides).
nA low HDL-cholesterol level, less than 1·00 mmol/L in men or 1·3 mmol/L in women (or if you are already on treatment to raise your HDL cholesterol).
nA high blood pressure: systolic greater than or equal to 130mm Hg and diastolic greater than or equal to 85mm Hg (or if you are already on treatment for high blood pressure).
n A raised fasting plasma glucose of greater than or equal to 5·6mmol/L.
If a patient presents with three or more of these risk factors together, their risk of cardiovascular problems and type 2 diabetes increases compared with someone presenting without metabolic syndrome.
The American Heart Association estimates that individuals with metabolic syndrome have a two-fold increase in risk for heart attack or stroke, and a five-fold increased risk for developing diabetes when compared with individuals who don’t have the syndrome.
In the developed world the syndrome is widespread. It increases with age and almost 40 per cent of people in the US and 30 per cent of people in Europe over the age of 50 have metabolic syndrome. Obese children can also develop metabolic syndrome.
Various influences seem to be involved such as a lack of physical activity and poor diets.
The syndrome can sometimes occur in lean individuals, suggesting that obesity is a marker for the condition, not the cause. Insulin resistance is thought to be a more likely cause, but research continues.
Your diet and lifestyle can affect and, in some cases, may resolve each of the risk factors associated with the metabolic syndrome.
Management may involve consultations with a dietitian and a practice nurse to discuss suitable dietary modifications, alcohol consumption, activity goals and smoking cessation. If lifestyle changes aren’t enough, your GP may prescribe medications to treat and control your risk factors.
The US National Cholesterol Education Program reports that the first-line therapy should be weight reduction if the individual is over
weight, reinforced with increased physical activity. “Weight loss lowers serum cholesterol and triglycerides, raises HDL cholesterol, lowers blood pressure and glucose, and reduces insulin resistance.” So losing weight – even as little as 7-10 per cent – can have a positive impact on all of the associated risk factors.
The Get Ireland Active guidelines advise that “if you have a very high BMI (30 or more), or you are extremely inactive, start with exercise bouts of 10 minutes or less. Gradually increase the duration, and then the intensity of your activity until you reach the adult guidelines.”
To avoid gaining weight, the guidelines advise that you need to use at least 350 calories a day in physical activity, as well as the energy you use in everyday tasks. This equates to about 60 minutes of brisk walking or 30 minutes of jogging a day.
This might look like a lot, but remember any activity above what you had been doing is an improvement.
A diet rich in fruit and vegetables, with moderate amounts of wholegrains, lean proteins, nuts and healthy oils (olive, rapeseed, camelina) may reduce your risk of heart disease.
A study conducted by Salas Salvado in 2008 found that after one year the incidence of metabolic syndrome was reduced by 6.7 per cent, 13.7 per cent and 2.0 per cent in the Mediterranean diet plus virgin olive oil; 30g/day mixed nuts plus the Mediterranean diet; and low-fat control diet, respectively.
The conclusion was that a traditional Mediterranean diet enriched with nuts could be a useful tool in the management of this syndrome. Remember to choose unsalted nuts and to keep your portion to about an ounce a day to avoid eating surplus calories.
A tailored nutrition plan can be devised by your dietitian to help you alter your personal risk factors.
There is good evidence that the risk of metabolic syndrome is substantially lower if you remain physically active, do not smoke, have a relatively low carbohydrate intake, moderate alcohol consumption and if you maintain a healthy weight for your height.
So if you have a high HDL cholesterol and no other risk factors, don’t sweat the small stuff.
On the other hand, if you have three of the risk factors for the metabolic syndrome, even if your doctor hasn’t used that term, ask yourself if is there anything you can do now to lower that risk.
Paula Mee is a dietitian at Medfit Proactive Healthcare and a member of the Irish Nutrition and Dietetic Institute.