Take heart, the time you eat matters too

That bowl of air-popped corn you think of as a healthy snack to munch on while watching television after dinner? The dark chocolate bar you treat yourself to after the kids have gone to bed? Those post-Chinese New Year pineapple tarts you scarf down at midnight?

Put that tart down now.

As if exercising regularly, eating healthily and maintaining good gut health were not enough, now comes a study showing that women are in danger of developing heart disease if they eat after 6pm.

According to the study by Columbia University, women who ate a higher proportion of their daily calorie intake after this time tended to have higher blood pressure, be more overweight and be less able to control their blood sugar levels. These are risk factors for heart disease.

There is worse.

For every 1 per cent increase in calorie intake after 6pm, the participants were more likely to have higher blood pressure, body mass index (BMI) and poorer glycaemic control.

The results were presented in November last year at the American Heart Association's Scientific Sessions.

The study involved 112 women with the average age of 33. They recorded what they ate, how much they ate and when they ate for one week at the start of the study, and again at the one-year mark.

Researchers also assessed their risk factors for heart disease - smoking, hypertension, high cholesterol, diabetes, obesity, physical inactivity and poor diet, at the start and at the end of one year.

The study showed that women who consumed more calories after 6pm and after 8pm had poorer heart health. Hispanic women made up 44 per cent of the participants, and researchers found a stronger association between evening calorie intake and higher blood pressure among them, compared with non-Hispanic women.

Time to reschedule dinner?

• Eat plenty of fruit and vegetables, whole grains, fish and high-fibre food.

• Limit salt intake to no more than one teaspoon or 2,000mg a day, by avoiding salted and preserved foods, limiting sauces and gravies, and using minimal salt and seasonings in your cooking.

• Opt for clear soup options when eating out and avoid deep-fried food.

• Avoid fatty foods such as fatty meat, butter and oil.

• Avoid high-glycaemic and calorie-laden food such as white rice, white bread, biscuits, pastries, French fries and chips.

• Eat regular meals with moderate portions. Skipping meals and binge-eating can cause blood sugars to spike and dip, causing low energy levels, frequent cravings and weight gain.

• When eating late is unavoidable, have a mix of complex carbohydrates and protein, such as whole-grain bread with nut butter or Greek yogurt with granola. Avoid eating fatty, spicy, sugary or acidic foods as they can cause indigestion.

• Have a snack before a late dinner and eat less at dinner.

• Skip caffeine as it can affect sleep.

• Do not eat two to three hours before bedtime, to prevent reflux and heartburn.

• Aim for 150 minutes of moderate physical activity a week.

• If overweight or obese, aim to get to a normal, healthy weight by cutting down on calories consumed and increasing the amount of physical activity to burn calories.

• Quit smoking.

• Screen yearly for hypertension, diabetes and high cholesterol levels, and treat these conditions early to get them under control.

• Avoid drinking too much alcohol.

• Manage stress levels and have good emotional and mental health.

Cardiologists and dietitians The Straits Times interviewed point to the small number of participants studied and the ethnic differences between them and those living in Singapore.

However, there is no escaping the fact that cardiovascular disease is the top killer of women in Singapore.

Dr Chan Po Fun, consultant for cardiology at Ng Teng Fong General Hospital, says: "Most people think heart problems are male-dominated. In truth, heart disease, particularly coronary artery disease, is the No. 1 cause of death of women in Singapore.

"Cardiovascular disease kills more women than all forms of cancer combined."

Assistant Professor Low Ting Ting, consultant (Department of Cardiology) and programme director (Women's Heart Health Programme) at the National University Heart Centre, Singapore, says cardiovascular disease claimed the lives of 2,635 women in 2018. Overall, one in three women dies from it.

Dr Chan says studies have shown that Indians are more prone to heart attacks and Malays are more susceptible to fatal complications after a heart attack.

So while the ethnic make-up of the participants in the Columbia University study differs from here, there are takeaways for Singapore women.

Dr Chan says: "Lifestyle approaches to good cardiovascular health have traditionally focused on what we eat and how much we eat. A lesser-known fact is that the timing of when we consume our calories is also critical in staying trim and fit.

"When food is consumed later in the evening, the body is more likely to store these calories as fat rather than burn them as energy.

"This translates into higher body mass index (BMI) and its associated metabolic diseases - raised blood pressure, elevated cholesterol levels, poor blood sugar control and plaque deposition within the arteries."

Ms Chow Pek Yee, head of the Department of Nutrition & Dietetics at Yishun Health, says: "It's possible that eating late could result in misalignment of our body master clock, leading to problems in metabolism that result in changes to the level of fasting blood sugar, higher insulin, higher marker of resistance to insulin and higher blood pressure.

"It is quite common - if we skip our breakfast, we tend to be hungry and eat more at dinner. Also, with the lower satiety in the evening, people tend to eat larger portions of food, but may still feel hungry and snack later on. So any extra calories would promote weight gain and obesity, leading to an increased risk to cardiovascular health, blood pressure, BMI and blood sugar.

"If we consume 50 extra calories a day over 365 days, that would lead to about an 18kg weight gain in a year."

Apart from poorer cardiovascular health, late eating can also have other consequences.

Ms Heng Mei Shan, a dietitian at Alexandra Hospital, says the body's ability to use insulin to control blood sugar declines over the course of the day.

"Late-night eating can also cause other problems such as acid reflux, heartburn and poorer sleep quality."

The wakefulness caused by late-night eating can spiral into a cycle of more late-night eating.

Prof Low says: "Studies suggest that sleep deprivation can lead to junk food cravings at night, which leads to increased unhealthy snacking at night, which then leads to weight gain.

"Sleeping early and having enough sleep may be a good way to keep off late-night eating."

With the demands of work and caring for children or elderly parents, it seems unrealistic for women to be wolfing down dinner before 6pm. What can they do to mitigate the effects of eating after that time?

Ng Teng Fong Hospital's Dr Chan says: "Eat breakfast like a king, lunch like a prince and dinner like a pauper. Sometimes, eating late cannot be avoided. Consuming a larger proportion of our daily caloric requirement during breakfast and lunch, and less during dinner, is an effective way to lessen the impact of late meals.

"Regular exercise also reduces post-meal insulin spikes and prevents excessive fat storage."

She suggests an early dinner with enough time for a post-meal stroll.

Yishun Health's Ms Chow says the kind of food people eat matters too.

She suggests food with bulk and fibre, such as fruit and vegetables, when eating late. Singaporeans should also watch their intake of fat, sugar and salt.

"According to the 2018 National Nutrition Survey, we are eating richer and sweeter foods. For every 1,000 calories, the food we eat has increased 11 per cent in total fat and 9 per cent in sugar, compared with the 2010 National Nutrition Survey.

"We take too much salt as well - about 90 per cent of Singaporeans exceed the recommended salt allowance. Most of our salt intake is from the sauces and seasonings in the food.

"We take an average of 9g of salt a day, although we are encouraged to consume less than 5g salt or one teaspoon a day."

So far, so grim. But sticking to these lifestyle choices can pay dividends.

Prof Low says: "There are many proven ways and lifestyle measures to stay heart-healthy. Many women do not know that cardiovascular disease is preventable 80 per cent of the time."