Cancer is Singapore's most common killer, accounting for 29 per cent of deaths each year since 2015.

Even with the advent of groundbreaking cancer treatments, some cancers still remain deadly and expensive to treat. This, coupled with a barrage of news claiming that everything from bacon to viruses can cause cancer, people may feel hopeless when it comes to protecting themselves from this debilitating disease.

However, studies have shown that there are still things you can do to reduce the risk of getting several types of cancers.

Below, we explore 5 of these prevention methods.

QUITTING SMOKING CAN REDUCE THE RISK OF DEADLY CANCERS

Smoking is one of the most well-known causes of many life-threatening illnesses. Because of this, Singapore has done quite a lot to reduce smoking and has seen measurable success: only 13 per cent of the adult population smokes-one of the lowest rates among developed countries.

Cigarettes contain dozens of carcinogenic chemicals that affect not just your lungs, but your mouth, stomach, blood stream and esophagus as well.

Studies have shown a strong correlation between smoking and the development of a variety of cancers. The main carcinogenic compounds in tobacco smoke believed to be responsible for cancer are polycyclic aromatic hydrocarbons (PAH) and N-Nitrosamines. PAHs are the very same compounds that form when things like coal, oil and garbage are burned.

Furthermore, researchers from the Shanghai Cohort study tested N-nitrosamines in adult male smokers and found that these compounds correlated with an increased esophageal and lung cancer risk. Thus, not smoking decreases your intake of these compounds and may lead to a lower risk of developing these types of cancers.

LIMITING ALCOHOL TO REDUCE ORAL, LIVER, RECTUM & COLON CANCER RISK

Just as with smoking, there is a strong positive link between alcohol consumption and cancer risk.

Many epidemiological studies show a causal link between heavy alcohol consumption and oral, liver, rectum and colon cancer. For example drinking more than 50g (about 5 standard drinks) per day resulted in a two to threefold risk of getting these cancers.

Despite these startling figures, alcohol consumption has been increasing in Singapore. The lifetime prevalence of alcohol abuse in Singapore increased from 3.1 per cent in 2010 to 4.1 per cent in 2016-a worrying trend considering alcohol's relationship with cancer.

The main reason why alcohol causes cancer stems from how your body metabolises it. When your body breaks down alcohol, it is eventually converted to acetaldehyde. Acetaldehyde is a toxic, carcinogenic and mutagenic compound that can damage proteins and DNA, potentially leading to cancerous cell mutations.

Furthermore, the effects of alcohol are long-lasting. Studies have shown that even after quitting drinking, cancer risk didn't decrease to the levels of those who never drank until a decade or more after quitting alcohol. This is in contrast to cigarette smoking, where quitting has almost immediate health benefits, such as improved blood pressure and better blood circulation.

Thus, while it may be tempting to go out and binge drink after a stressful work-week, you will really be better off in the long-run by relaxing with a non-alcoholic drink instead. If you really need to drink, we recommend sticking to the daily recommended limits. Not only that, but cutting back on your drinking can have a significant financial benefit. We found that by cutting your drink outings by half, you can save around $1,500 per year.

MAINTAINING A HEALTHY BODY WEIGHT CAN REDUCE THE RISK OF SEVERAL TYPES OF CANCER

Obesity lends itself to a myriad of health problems, ranging from heart disease to cancer. However, with the global population seeing a rising rate in obesity, it is important now more than ever to stress the importance of maintaining a healthy weight.

Epidemiological studies have suggested that overweight or obese people may be at an increased risk for colon, endometrial, kidney, liver, gallbladder, non-Hodgkin lymphoma, leukemia and pancreatic cancer. Why is this? Excess body fat leads to chronic inflammation, insulin resistance and hormonal changes, all of which can increase the risk of tumour growth. For instance, a Framingham study showed that overweight people have a 50-240 per cent increased risk of getting colon cancer compared to individuals with healthy waist circumference.

If you are at risk of being overweight, it is recommended to clean up your diet by increasing your intake of vegetables and fruit, swapping processed meat for lean protein such as fish and chicken breast, and reducing sugar.

You should also consider increasing your daily activity level by taking up a class at the gym or going for walks throughout the day. You don't even have to go to a fancy boutique gym to get your recommended dose of exercise. Singapore also has plenty of affordable gyms that start at just $133 per month that offer most of the same equipment and classes as higher end options.

CRUCIFEROUS VEGETABLES MAY REDUCE RISK OF SEVERAL TYPES OF CANCER

While as a kid you may have felt like being forced you to eat your vegetables was a mild form of torture, your parents actually had your best interests at heart. Beyond being packed with nutrients, cruciferous vegetables, such as broccoli, bok choy cabbage, kale and cauliflower have been shown to potentially reduce the risk of hormone-sensitive cancers.

Not only do cruciferous vegetables (CF) contain vitamins that are essential to your health, but they also contain compounds that may have strong anticancer properties. These compounds include I3C and sulforaphane, which can help induce programmed cell death, inactivate carcinogens and protect cells from DNA damage.

However, while the results have been generally positive, research still needs to be done to find absolutely conclusive evidence for all cancers. For instance, one study in particular showed that while there was no reduction in cancer risk among people who already consumed a lot of CF, there was an increased risk of colon cancer among individuals who ate very little amounts of vegetables.

Nonetheless, while research to confirm the benefit of cruciferous vegetables is still being conducted, there is enough evidence to suggest that adding these vegetables to your diet may improve your overall health and reduce the risk of certain types of cancers.

FLAXSEED MAY REDUCE THE RISK OF BREAST CANCER IN POST-MENOPAUSAL WOMEN

Food marketers have long been capitalising on the current health trend by promoting "superfoods" that promise to completely cure everything from acne to cancer. However, there hasn't been enough conclusive evidence to definitively prove any one food can cure or prevent disease.

Despite this, there have been promising results when it comes to how compounds in certain foods interact with cancer cells in certain cancer-based studies. Flaxseed, for instance, is one food that has shown promise in reducing the risk of breast cancer.

Several animal studies found that flaxseed may reduce growth and proliferation of human breast cancer cells. This is thought to occur because flaxseed contains secoisolariciresinol diglucoside (SDG) lignans.

Lignans are a plant compound that can change estrogen metabolism and reduce the chance that damaged cells reproduce-potentially preventing tumour growth. Furthermore, flaxseed may be a good dietary addition when taking cancer drugs. In a University of Toronto study, a diet of flaxseed in combination with Tamoxifen (a breast cancer drug) inhibited the growth of ER+ human breast cancer cells in mice more successfully than Tamoxifen alone.

However, flaxseed studies show promising results not just in animals. Clinical studies found that post-menopausal women and overweight premenopausal women who ate a high lignan diet saw a decreased risk of breast cancer. Furthermore, a double blind clinical trial also found that post-menopausal women with breast cancer who ate flaxseed had an increased rate of cancer cell death and decreased tumour cell proliferation.

Thus, these studies show that lignan-rich foods can be associated with a decreased risk of breast cancer in postmenopausal women and has the potential to reduce human breast cancer cell growth. However, as with all foods, further clinical studies still need to be done to definitively prove the relationship between lignans and cancer risk. Additionally, you should be careful not to overeat flaxseed and instead aim for the recommended 2-3 tablespoons per day of the ground variety.

IMPORTANT FACTORS TO KEEP IN MIND

Due to our still limited knowledge about cancer and the difficulty in definitively measuring cancer risk, cancer risk reduction methods are still being investigated. Thus, with the exception of smoking and alcohol consumption, the aforementioned prevention methods should be used as guidelines and as part of a healthy and active lifestyle.

You should always consult with your doctor before drastically changing your diet or exercise regime to ensure the changes are suitable for you. Furthermore, cancer is incredibly expensive to treat, with cancer treatment costing upwards of $100,000 per year. Thus, you should make sure you get regular cancer screenings and consider purchasing a comprehensive health insurance policy to have financial protection in the event of diagnosis.

Overall, as with most illnesses, prevention is the best method both health-wise and financially.

This article was first published in ValueChampion.