It’s Thanksgiving time in Canada, so what better time to write about how eating affects your health.

Depending on what and how much you eat, big holiday dinners can add up to 3000, 5000, or even 7000 calories – several days of your caloric needs in one sitting.

In fact, in North America, dinners are usually the largest meal, and it’s quite easy to consume your an entire day’s worth of calories just at dinner – nevermind the other meals and snacks you had during the day.

So if you’re looking to cut back, lose a bit of weight, and cut down your belly size a bit, the logical place to start might be the last meal of the day.

But is it healthy?

This topic is a highly controversial one, and like most topics, there are good scientific studies backing up both sides of the argument.

The traditional school of thought is that it’s best to eat many small meals constantly during the day. This is thought to prevent cravings and avoid binging. The problem is that this tends to work better for active people – which most people aren’t. The other problem is that people tend to vastly overestimate what a “small” snack is and end up eating even more than normal.

More recent studies suggest that there is actually a benefit to short-term fasting, or at least drastically reducing caloric intake for periods of time. Apparently fasting may help with insulin resistance, and reduce inflammation.

I found a good summary of two recent studies here:

The thinking behind this is that the digestive system needs some time to rest and heal itself every so often, and doesn’t get a chance if you keep packing in the food 247.

You make have heard the old saying “Eat breakfast like a king, lunch like a prince, and dinner like a pauper.” I’ve been following this advice lately and found it gives me pretty balanced energy during the day.

I’ve also experimented with fasting and found that I can easily go without food for 24 hours, maintaining full energy and mental clarity – as long as I drink lots of water. The water is really important, since you generally derive a lot of your daily water intake from food (even bread is about 50-60% water). You need to drink much more when you’re fasting. I suspect often times when people think they’re hungry, they’re actually just thirsty or dehydrated.

There are obviously a lot of factors involved, but my personal leaning is that periodic caloric restriction or fasting is better than eating tiny meals and snacks constantly. In the end, however, the science is split, and a lot of it just comes down to calories in and calories out.

Exercise more, eat less, and make sure your food is nutrient-dense – go for fresh fruits and vegetables, 100% whole grains (don’t get fooled by “multi-grain” crap), and non-saturated fats.

Avoid “comfort” foods – usually nutrient-void dense carbs and/or sugar. That’s a sure way to pack on the pounds. And don’t eat when you’re bored or watching television. Go for a walk instead!

Finally, in my opinion, feel free to skip dinner or just have a light snack at night, but then, make sure to have a substantial, nutritious breakfast the next day – not just a muffin or granola bar (both of which are essentially “empty” calories).

I’d love to hear additional thoughts and comments about this – especially links to related research study results.

Have a Happy and Healthy Thanksgiving! :)