"The happiest people in the world interact about 7 hours a day," says Dan Buettner, author of Thrive: Finding Happiness the Blue Zones Way. "They don't just wake up in the morning and schedule 7 hours of interaction. A lot of it happens to revolve around food and the rituals that surround food." Buettner circled the globe in search of the world's happiest populations. He shared four tips from different countries.

Dan Buettner Dan Buettner Photo: eschipul / Flickr

1. Denmark: Toast with your eyes

Denmark is the happiest place in the world, especially in and around Aarhus. They have these long, dark winters, but a couple of times a week they'll create an environment where people gather around candlelight. They’ll sit around a small table and they’ll have open-faced sandwiches they call smorrebrod, pate, herring and cheese.

There's an interactive nature to it. Instead of just clinking their glasses in the middle, before they drink, they always look each other in the eyes. There’s a human interactive element to the whole food ritual.

2. Singapore: At the table, cook, eat and interact

In Singapore, there is a ritual around something called the steamboat. There will be a bubbling pot of stock, and people will put raw meat or raw vegetables in it. It becomes an opportunity to interact.

3. Mexico: Don't let work get in the way of 'sacred' food time

In northeastern Mexico, they eat carne asada: beef or pork marinated in lime juice and cilantro. People stand around and make tacos out of it. They’ll make a sauce out of serrano peppers, cilantro, garlic and tomatoes, and wash it down with cold beers. Very rarely will work ever get in the way of that carne asada; there's a sacred time where people interact around that food.

4. The United States: Start your day right (with oatmeal for breakfast, 'you'll be 20-30 percent happier all day long')

Thrive Thrive

If we start our day with a grease-and-meat-laden breakfast like bacon and eggs, we'll have less energy during the day, we'll get less oxygen to our brain and we'll be more sluggish.

Start your day with a food high in complex carbohydrates and omega-3 fatty acids. I assert that the very best meal to start your day -- if happiness is what you're interested in -- is oatmeal. Regular, steel-cut oatmeal, slow-cooked, will actually help your brain get more tryptophan, which we know is a happiness hormone, and omega-3 fatty acid, which is also a very good antidepressant.

If you put walnuts in your oatmeal, that makes it even better. Start your day with oatmeal and walnuts and you'll be 20-30 percent happier all day long.