Is regular yoga practice a good way to lose weight?

Does yoga practice affect the food we choose to eat?

by guest author Jude Mahood, nutritionist and yoga teacher

I often get asked whether yoga practice is a good way to lose weight. I would love to be able to reply, unreservedly, “Yes. Yoga melts away the kilos’.  It would certainly be great for business, but it wouldn’t be ethical because it is not 100% truthful.

In my experience, people inquiring about yoga and weight loss really want to know about the physicality of yoga in regards to calorie-burning.

Fair enough since how much you weigh is determined by calorie balance. In a nutshell, when energy intake (what you eat) equals energy expenditure (your activity), you maintain your weight.

But if your dietary intake is greater than your activity output, you will gain weight. And you’ve guessed it – the only way to lose weight is to eat less or to be more active, or better still, do both.

As long as you’ve created a calorie deficit (burning off more calories than what you’ve taken in) you will lose weight. It doesn’t matter what type of food you eat or what type of “diet” you go on, you will not lose weight until you’ve tipped the caloric balance in favour of weight loss. Even the much touted Atkins diet, which was extremely popular until a drop in the number of people following the diet combined with falling sales of its low carbohydrate products brought it close to bankruptcy, only worked because it created a calorie deficit. People probably got bored with the limited choice of food and ate less. There was nothing magical about it.

So getting back to yoga, the evidence to date says that, in general, it is not intense or aerobic enough to have a significant effect on weight loss. This is based on the assumption that yoga is not typically a vigorous activity. If you do a gentle 60-90 minute class each week, it most likely will not result in weight loss.

But on the other hand, if you’re doing an energetic vinyasa practice several times a week, including lots of sun salutations, warrior poses and backbends, then it would result directly in some weight loss. It’s really hard to put an exact number on it, but it has been estimated that a moderately vigorous 60 minute class would probably burn around 250-400 kcal.

Putting this into perspective, to loose ½ kg a week, you would have to burn off 500 kcal more (or take in 500 kcal less) each day. An apple is about 65 kcal, a regular sized Moro bar is 265kcal, a CookieTime chocolate chip biscuit is 447kcal, and a small glass of red wine (100ml) is about 90kcal. So keep in mind that any resulting weight loss would also depend on what you had to eat or drink after your yoga class.

But there is an interesting twist to the yoga-weight loss story that was highlighted in a recent study published in the Journal of the American Dietetic Association. Knowing that yoga doesn’t typically burn much in the way of calories, the authors were curious as to why, in one of their previous studies, even gentle forms of yoga had led to weight loss. Their conclusion was that it was due to an increase in body awareness that yoga practice fosters. This increased sensitivity, specifically to hunger and satiety signals, resulted in what they termed, “mindful eating”.

Now as a yoga teacher, inner awareness and mindfulness is what yoga practice is all about, so there are no real surprises there. But I am also aware that mindfulness does not always continue off of the mat. And as a nutritionist I am even more aware of the external forces that continually try to divorce us from our internal, physiological cues.

So what are these internal signals that we need to tune into?

Let me begin by saying that appetite is complex. Put in simple terms, it is about balance between the hormone that make us feel hungry (ghrelin) and the one that makes us feel full (leptin). If they are working properly, then we eat when we’re hungry and we stop when we’ve had enough. (The ghrelin-producing cells are the ones that are cut away in stomach reduction surgery, sending the hunger drive into a nose-dive).

But as I said earlier, appetite is complex and other factors come into play besides these hormones. We also eat because of emotions and because of influences from external cues that can override our internal signals. Yoga aids weight loss by getting us back in touch with these internal cues. If we listen to our body and let it do what it is meant to do, we will naturally gravitate toward our ideal weight.

How do you draw attention to the internal cues in your students?

We probably all do it to some extent already. When I am teaching a yoga class, I encourage people to listen to their bodies. The key to listening is becoming aware and constantly fine-tuning that awareness to more and more subtle sensations. If practice is approached with focus and awareness, you become more tuned-in and connected to your body.

But, if you are thinking about what you will wear to work tomorrow, for example, while holding Parsvokonasana, you will not learn anything about yourself. Is the breath supporting the pose; are you feeling energized or drained; should you soften more or move closer to your edge; is there discomfort anywhere, and if so, is it a good or a bad feeling?

I also steer away from mirrors, although I do drag one out occasionally because I think it can be a good learning tool. But if students focus solely on what they look like, it becomes just another external cue, distracting them from developing their inner awareness. If this process of internalizing, while holding an asana, can stay with the person even when they are off of their mat, it becomes an effective strategy for countering external appetite cues.

Next time you are walking past the Golden Arches and get a whiff of a Big Mac, ask yourself if you are actually hungry before getting sucked in. Become aware of your bodily sensations and then make your decision based on what you find when you turn your awareness inwards. It may be that you are hungry and decide to have something to eat, but at least you, not the golden arches, were in control.

If you take the time to inquire, you may also find that the attraction to the Big Mac was based on something emotional, rather than on hunger itself. Yoga practice encourages us to become aware physically, mentally and emotionally. You learn a lot about yourself through the process of internalizing, and in regards to weight loss, you learn a lot about what drives you to eat.

Another way in which yoga is thought to help with weight loss is by encouraging people to accept sensations, even if they may be unpleasant. For example, some asanas, and the warrior ones come to mind here, teach students that they can be comfortable with discomfort. They can breathe through it and know that they will survive it and in fact, feel better for it. They don’t have to give up as soon as discomfort sets in. And again, this strategy can be taken with them off of the mat.

As the authors of the study on mindfulness suggest:

When you go home after yoga class and open up the fridge and see a chocolate cake, you have the resources to stay with the discomfort of not eating that chocolate cake.

I would also add that yoga just plain makes you feel good! And if you feel good about yourself and like yourself, then you are much more concerned about what you do or don’t put into your body.

Another possible way in which yoga helps with weight loss, independent of mindfulness, is the ability for yoga to help with insomnia. Students often report that yoga helps them to sleep better. Some research has shown that disrupted or insufficient sleep plays havoc on the appetite hormones, decreasing leptin (the hormone that lets us know we are full) and increasing ghrelin (the hormone that tells us we are hungry). Less than seven hours of sleep per night makes you more prone to becoming overweight and it has been suggested that people who only gets six hours per night are 23% more likely to be obese!

So in summary, yoga may lead to weight loss if it is vigorous and practiced regularly. But weight loss is more likely the result of mindfulness that yoga fosters, the yoga feel-good factor that makes you want to invest in your health, and maybe, indirectly, because of improved sleep.

Weight loss is more likely to be successful when yoga practice accompanies, rather than replaces, traditional weight loss regimes. Part two of this article will look at specific nutrition strategies that work alongside mindfulness.

Jude is a yoga teacher, Registered Nurse and Registered Nutritionist. She works as a research nutritionist at the University of Otago and teaches yoga from her studio in Dunedin. She describes herself as a “foodie” and is an active a member of Slow Food Otago.