Eating to feel better

Research findings are clear: We feel better not just physically, but also emotionally and mentally, when we exercise (read these articles from the American Psychological Association and Harvard Medical School to understand the science behind the claim).

But what we eat may also play a role. Specifically, certain foods can be helpful for enhancing our mood (here’s the rough guide). Here’s what the research says:


1. Chocolate
It’s official. Dark chocolate is good for you. This is not just because it’s been reported widely in the media (e.g., CNN, Science Illustrated, Psypost). But it’s because a 2013 random controlled double-blind study showed that healthy adults given a daily high dose of cocoa polyphenols reported better mood at the end of the month than their peers who were given a placebo.

2. Oats and barley
Apart from the wholegrain benefits of eating complex carbohydrates, oats and barley are also good sources of folate, which is important for producing neurotransmitters which in turn control mood.

3. Lentils and beans
Lentils and beans provide not only dietary fibre and a low-GI (glycaemic index) complex carbohydrate meal option, they are also good sources of folate. This means pinto, borlotti, cannellini, and black beans, as well as chickpeas. Even mung beans are rich in folate (good ol’ tau suan).

4. Leafy greens and avocado
Folate, B6, and B12, are important for the production of neurotransmitters (e.g., serotonin) involved in mood regulation. Mangoes, avocado, and asparagus are also good sources of folate. B6 is naturally found in dark leafy greens, papaya, and orange, while eggs, cheese, and fish are good sources of B12. So Popeye was right after all: Spinach is good for you.

5. Tofu, flax seeds, and walnuts
Omega-3 fatty acids are reported to directly affect serotonin regulation (here’s the scientific explanation) and are found to affect mood. Other studies indicate incorporating omega-3 rich foods into one’s diet (typically oily fish such as salmon, mackerel, sardines) has a positive effect on mental wellbeing. Flax seeds, walnuts, tofu, and scallops are excellent sources of this highly sought after fatty acid.

Time out!

That chronic stress is responsible for poor immune functioning has been long established. The literature as early as 1990s provides much evidence to support this view (O’Leary, 1990; see Khansari, Murgo, & Faith, 1990 for a review), while more recent research indicates a role for moderating factors such as the ageing process or physical illness, which increase our vulnerability to immune suppression in the face of chronic stress (Segerstrom & Miller, 2004).

The finding that chronic stress has long-lasting negative consequences for our cognitive abilities is also not new. It’s been well-established that prolonged exposure to stress damages our hippocampus – a brain structure responsible for consolidating short-term memory to long-term memory (McEwen, 2004Sapolsky, Krey, & McEwen, 1986).

It follows that efforts to manage chronic stress should be equated with improvements in mental wellbeing measures such as life satisfaction and psychological mood. Apart from specific interventions targeted at alleviating the symptoms of depression, research points to exercise as an effective strategy for managing stress. Various studies demonstrate that exercise improves mood and anxiety levels (Craft and Perner 2004Ströhle, 2009; see also Atlantis, Chow, Kirby, & Singh, 2004Bhui, Dinos, Stansfeld, & White, 2008Coulson & McKenna, 2008Daley & Parfitt, 2011). Additionally, there is some evidence that participation or passive appreciation of creative cultural activities can also have a positive effect on mental wellbeing, specifically psychological mood (Cuypers, Krokstad, Holmen, Knudtsen, Bygren, & Holmen, 2011).

So if you’re stressed and need some time out, here are some ideas to take home and share with your family and friends:

1. Get up and get going!

  • Walk down Orchard Road in the evening for some physical exercise. Enjoying the Christmas lights are an optional add-on.
  • Jostle the crowd at Sitex 2013 held at Singapore Expo. 28 Nov to 1 Dec. Playing the game of walking quickly through the throng, visiting every booth, and avoiding contact with other people earns you extra physical activity points.
  • Join the dots and map out all the hip and cool cafes and historical landmarks on this National Heritage Trail in Tiong Bahru, which has recently received new media attention.

2. Take time out and enjoy what’s out there!

3. Do it as a family activity

  • The Singapore Zoo celebrates its 40th birthday by giving their macques and chimps enrichment gifts (read: a puzzle containing delicious food). On weekends till 22 Dec 2013, at 80 Mandai Road.
  • Visit the ice sculptures exhibiting as part of the International Ice and Snow Sculpture Festival, at Sheares Link. 30 Nov to 4 Dec 2013. $26-32. Don’t forget to wear your coat, scarf, and gloves!
  • Sleep over with your little (and not-so-little) ones at the SEA Acquarium on 17-18, 23-24 Nov, 6-7 and 14-15 Dec. $135-158 for non-members.

Food for Thought

At least one in ten persons aged 18 to 69 years has diabetes mellitus in Singapore, according to the 2010 Singapore Burden Of Disease Study (MOH), while prevalence for older adults is one in three persons (“1m diabetes by 2050 as Singaporeans get older, fatter”, Straits Times, 2 Oct 2012). This is relatively higher than the global prevalence which the International Diabetes Federation puts at 8.3% in 2011. Metabolic syndrome, which is closely associated with diabetes, has a relatively high prevalence in Singapore, particularly when body mass indices (BMIs) relevant to Asian body build are applied (read this IDF report).

A local report on diabetes from the Health Promotion Board reveals a relatively high proportion of residents with undiagnosed diabetes. And not surprisingly, a local study of 43,176 adults aged 45 to 74 years revealed that among non-smokers, a greater intake of fruits, vegetables, and soy foods was associated with a lower risk of type II diabetes (Odegaard et al., 2011).

There’s also much hoo-ha at the moment about soda tax and sugar tax. While more fingers are being pointed at sugar as the villain in the landscape of obesity, metabolic syndrome and diabetes, saturated fat isn’t entirely off the hook. True, fructose contributes to insulin resistance while not providing adequate satiation (“Sweet poison: Why sugar is ruining our health”, Telegraph, 12 April 2013; read also “Sugar, not fat, exposed as deadly villain in obesity epidemic”, The Guardian, 20 Mar 2013). But, intake of saturated fat is still associated with higher risks of heart disease (“Fat, Sugar or Carbs: Which Is the Bad Guy?”, Huffington Post, 25 Oct 2013). The good news about soda and sugar taxes is the expectation that obesity would be reduced in the states and cities they’re being applied, even though the debate rages on, and on, and on.

On World Diabetes Day (14 Nov 2013), there’s no time like the present to think about healthy eating. Here’s some thoughts about food:

1. Less is more. 

Here’s one diet to aspire to. Studies indicate that the diet structure of Okinawans is responsible for their successful ageing: They eat lots of fruits, vegetables, and soy products (“The Okinawan diet – could it help you live to 100?”, The Guardian, 19 June 2013). But more importantly, it may be their habit of eating until they feel 80% full: It’s their caloric restriction which may be making the big contribution (for details Willcox et al., 2006; 2007). If you’re not convinced, watch this TED talk.

2. Is there something worse than fructose? Yes, artificial sweeteners. 

Having a sugar substitute when we desire sugar seems to have the opposite desired effect. As neatly pointed out in a Harvard Health Blog, “Artificial sweeteners: sugar-free, but at what cost?”, there are at least two problems with artificial sweeteners. One is that we are tempted to eat other foods in place of the calories which we didn’t consume. The other is that sugar substitutes don’t provide the endorphins that sugar does and we continue to crave sugar. As a result, we still eat cake after a sugar-free drink. More disturbing facts are easily available at the eloquent Dr Oz website and videos which might help you switch off the “zero-sugar” option.

3. Eat like a caveman. But only if you’re prepared to cook like one?

The paleo diet. It’s the new black. There are apparently benefits to this diet (“5 reasons to follow a caveman diet”, Discovery; “6 health lessons from the paleo diet”, Huffington Post, 13 Sept 2013), and scientific evidence that this diet may have benefits for type 2 diabetes (Klonoff, 2009), possibly because it is more satiating than mediterranean diets (Jonsson et al., 2010). Well, at least it is a proponent of a “whole grains, fruits, and vegetables” diet. And to be a caveman, it would be preferable if one would also grow one’s own herbs, whip up pancakes without electricity, and knead one’s bread too. Not difficult to achieve at all.

4. Breakfast is the most important meal of the day.

The old adage isn’t wrong. A recent report (“Breakfast is the most important meal of the day”, Daily Mail, 23 July 2013) suggested that those who skip breakfast tend to have larger meals during the day, which predisposes them to heart attacks. Another recent study (by Odegaard and colleagues) indicated that eating breakfast frequently lowers the risk of obesity, metabolic syndrome, and diabetes mellitus (“The most important meal?”, press release, UM Minnesota, 16 Sept 2013). More importantly, there’s evidence that a low glycaemic index breakfast (like oats) helps children maintain their attention on cognitive tasks through the morning (Ingwersen et al., 2007; Wesnes et al., 2003).

5. We’re more likely to eat it if we’ve tried it before.

There’s a reason why healthy cooking demonstrations are part of a healthy eating programme at the workplace. One study which asked 205 participants to sample a chicken-and-whole-grain pasta dish and gave them the opportunity to try it at home with a receipe provided to them, found that they were more likely to perceive whole grains positively and to report more confidence about consuming them, compared to controls (Yao et al., 2013). Time for you to try out the recommended roasted brussel sprouts on the Food Network channel and the latest recipes on the Dr Oz show (like sweet potato peanut cookies!).

Why exercise works

We know the health benefits of physical activity. Better BMI, lower levels of LDL and higher levels of HDL, improved blood pressure and heart rate, more efficient cardio functioning, lower risk of cardiovascular diseases and diabetes. In addition, there are psychological benefits from exercising. It’s not only responsible for positive outcomes such as lower levels of stress and better life satisfaction in the general population, it’s also been shown to be effective in helping to improve psychological mood and mental wellbeing among those with depression (Ströhle, [2009] offers a comprehensive literature review on the subject).

And we know the health benefits of eating healthy. Health magazines and newspaper articles extol the virtues of making healthier eating choices, while there’s plenty of research evidence that increasing one’s daily intake of multigrains and/or greens plays a protective role against cancer, cardiovascular diseases, and obesity.

But knowing and doing are two different things. Perhaps it might be helpful to understand why exercise and healthy eating achieves these things. For one thing, it appears that exercise helps the body process fat more efficiently. A recent news article, “Altered states” (Economist, July 2013) highlights the finding that fats cells of people who exercise behave differently from those of people who exercise rarely (Ronn et al., 2013). For another, increased intake of greens appears to increase gut bacteria associated with healthy metabolism and decrease gut bacteria associated with obesity. The recent news article, “Wider understanding” (Economist, September 2014) explains that a high glycaemic diet impairs insulin functioning, unlike a low glycaemic diet (driven by the intake of multigrains) which in turn is protective against obesity.

But knowing the health benefits of exercise and healthy eating is half the equation: you still have to get out there and do it!