Have you had a blood test to check your cholesterol level? These check the different blood fat components:

• total cholesterol
• LDL (low-density lipoprotein), which is sometimes called “bad cholesterol”
• HDL (high-density lipoprotein), which is sometimes called “good cholesterol”
• triglycerides.

Your clinician then compares your test results to normal ranges – and may use ratios to compare different types of cholesterol.

High blood cholesterol is a major risk factor for cardiovascular disease. This is a broad term that includes disease of blood vessels throughout the body, arteries in the heart (known as coronary heart disease), heart failure, heart valve conditions, arrhythmia and stroke.

So what does cholesterol do? And what does it mean to have a healthy cholesterol ratio?

What are blood fats?

Cholesterol is a waxy type of fat made in the liver and gut, with a small amount of pre-formed cholesterol coming from food.

Cholesterol is found in all cell membranes, contributing to their structure and function. Your body uses cholesterol to make vitamin D, bile acid, and hormones, including oestrogen, testosterone, cortisol and aldosterone.

When there is too much cholesterol in your blood, it gets deposited into artery walls, making them hard and narrow. This process is called atherosclerosis.

Cholesterol is packaged with triglycerides (the most common type of fat in the body) and specific “apo” proteins into “lipo-proteins” as a package called “very-low-density” lipoproteins (VLDLs).

These are transported via the blood to body tissue in a form called low-density lipoprotein (LDL) cholesterol.

Excess cholesterol can be transported back to the liver by high-density lipoprotein, the HDL, for removal from circulation.

Another less talked about blood fat is Lipoprotein-a, or Lp(a). This is determined by your genetics and not influenced by lifestyle factors. About one in five (20%) of Australians are carriers.

Having a high Lp(a) level is an independent cardiovascular disease risk factor.

Knowing your numbers

Your blood fat levels are affected by both modifiable factors:

• dietary intake
• physical activity
• alcohol
• smoking
• weight status.

And non-modifiable factors:

• age
• sex
• family history.

What are cholesterol ratios?

Cholesterol ratios are sometimes used to provide more detail on the balance between different types of blood fats and to evaluate risk of developing heart disease.

Commonly used ratios include:

1. Total cholesterol to HDL ratio

This ratio is used in Australia to assess risk of heart disease. It’s calculated by dividing your total cholesterol number by your HDL (good) cholesterol number.

A higher ratio (greater than 5) is associated with a higher risk of heart disease, whereas a lower ratio is associated with a lower risk of heart disease.

A study of 32,000 Americans over eight years found adults who had either very high, or very low, total cholesterol/HDL ratios were at 26% and 18% greater risk of death from any cause during the study period.

Those with a ratio of greater than 4.2 had a 13% higher risk of death from heart disease than those with a ratio lower than 4.2.

2. Non-HDL cholesterol to HDL cholesterol ratio (NHHR)

Non-HDL cholesterol is the total cholesterol minus HDL. Non-HDL cholesterol includes all blood fats such as LDL, triglycerides, Lp(a) and others. This ratio is abbreviated as NHHR.

This ratio has been used more recently because it compares the ratio of “bad” blood fats that can contribute to atherosclerosis (hardening and narrowing of the arteries) to “good” or anti-atherogenic blood fats (HDL).

Non-HDL cholesterol is a stronger predictor of cardiovascular disease risk than LDL alone, while HDL is associated with lower cardiovascular disease risk.

Because this ratio removes the “good” cholesterol from the non-HDL part of the ratio, it is not penalising those people who have really high amounts of “good” HDL that make up their total cholesterol, which the first ratio does.

Research has suggested this ratio may be a stronger predictor of atherosclerosis in women than men, however more research is needed.

Another study followed more than 10,000 adults with type 2 diabetes from the United States and Canada for about five years. The researchers found that for each unit increase in the ratio, there was around a 12% increased risk of having a heart attack, stroke or death.

They identified a risk threshold of 6.28 or above, after adjusting for other risk factors. Anyone with a ratio greater than this is at very high risk and would require management to lower their risk of heart disease.

3. LDL-to-HDL cholesterol ratio

LDL/HDL is calculated by dividing your LDL cholesterol number by the HDL number. This gives a ratio of “bad” to “good” cholesterol.

A lower ratio (ideal is less than 2.0) is associated with a lower risk of heart disease.

While there is lesser focus on LDL/HDL, these ratios have been shown to be predictors of occurrence and severity of heart attacks in patients presenting with chest pain.

If you’re worried about your cholesterol levels or cardiovascular disease risk factors and are aged 45 and over (or over 30 for First Nations people), consider seeing your GP for a Medicare-rebated Heart Health Check.

Clare Collins, Laureate Professor in Nutrition and Dietetics, University of Newcastle and Erin Clarke, Postdoctoral Researcher, Nutrition and Dietetics, University of Newcastle

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Whether it’s your first or fourth cold of the season, many Australians are waking up at the moment with a sniffle, a sore throat or feeling more tired than usual.

June to August is peak flu season in Australia. There are also high rates of COVID circulating, along with other respiratory viruses such as respiratory syncytial virus (RSV) and adenovirus.

Sometimes it’s clear when you need to spend the day in bed: you have a fever, aches and pains, and can’t think clearly. If it’s the flu or COVID, you’ll want to stay away from others, and to rest and recover.

But what about if your symptoms are mild? Are you sick enough to take the day off, or should you push through it? And what if you feel pressured to work?

Here’s what to consider.

Are you likely to spread it?

While it may seem like a good idea to continue working, especially when your symptoms are mild, going to work when infectious with a respiratory virus risks infecting your co-workers.

If you are in a client-facing role, such as a teacher or a salesperson, you may also infect others like students or customers.

The risks may be even greater for those working with vulnerable communities, such as in aged care work, where the consequences can be severe.

From an organisational perspective, you are likely less productive when you are not feeling well.

So, whenever possible, avoid going into work when you’re feeling unwell.

Should I work from home?

The COVID pandemic normalised working from home. Since then, more people work from home when they’re unwell, rather than taking sick leave.

Some employees join Zoom or Teams meetings out of guilt, not wanting to let their co-workers down. Others – and in particular, some men – feel the need to maintain their performance at work, even if it’s at the expense of their health.

A downside of powering through is that workers may prolong their illness by not looking after themselves.

Can you take leave when you need it?

Employees in Australia can take either paid or unpaid time off when they are unwell.

Most full-time employees get ten days of paid sick leave per year, while part-time employees get the equivalent pro-rata.

Employers can ask for reasonable evidence from employees to show they are unwell, such as asking for a medical certificate from a pharmacy or GP, or a statutory declaration. The type of evidence required may differ from organisation to organisation, with some awards and enterprise agreements specifying the type of evidence needed.

While taking a sick day helps many workers recuperate, a significant proportion of workers engaged in non-standard work arrangements do not receive these benefits. There are, for example, 2.6 million casual employees who don’t have access to paid sick leave.

Similarly, most self-employed people such as tradies and gig workers do not have any paid leave entitlements. Although these workers can still take unpaid leave, they are sacrificing income when they call in sick.

Research from the Australian Council of Trade Unions has found more than half of insecure workers don’t take time off when injured or sick.

So a significant proportion of workers in Australia simply cannot afford to call in sick.

Why pushing through isn’t the answer

“Presenteeism” is the phenomenon of people reporting for work even when they are unwell or not fully functioning, affecting their health and productivity.

While exact figures are hard to determine, since most organisations don’t systematically track it, estimates suggest 30%–90% of employees work while sick at least once a year.

People work while sick for different reasons. Some choose to because they love their job or enjoy the social side of work – this is called voluntary presenteeism.

But many don’t have a real choice, facing financial pressure or job insecurity. That’s involuntary presenteeism, and it’s a much bigger problem.

Research has found industry norms may be shaping the prevalence of “involuntary presenteeism”, with workers in the health and education sectors more likely to feel obligated to work when sick due to “at work” caring responsibilities.

What can organisations do about it?

Leaders set the tone, especially around health and wellbeing. When they role-model healthy behaviour and support time off, it gives others permission to do the same.

Supportive leaders can help reduce presenteeism, while pressure from demanding leaders can make it worse.

Your co-workers matter too. When teams step up and share the load, it creates a culture where people feel safe to take leave. A supportive environment makes wellbeing a shared responsibility.

But for some workers, leave isn’t an option. Fixing this requires policy change across industries and society more broadly, not just inside the workplace.

Alex Veen, Senior Lecturer and University of Sydney Business School Emerging Scholar Research Fellow, University of Sydney; Hannah Kunst, Lecturer in Leadership, University of Sydney, and Nate Zettna, Lecturer in Leadership, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.