We had a simple back-yard barbecue this weekend, just a handful of good friends over for burgers and dogs, chips and macaroni salad, watermelon and other fresh fruit, some sodas and beer. (I did not, I regret to tell you, follow the great advice from Ellie Krieger about creating a better barbecue that I wrote about a few weeks ago.)

Propriety argues against my complaining about how much that simple, and not particularly healthful, spread cost. But it was so much, it made me wonder how many such parties are in our future. I’m sure I’m not alone in that.

Nor am I alone in finding it increasingly pricey to feed my family the more-healthful fare we try to eat most days of the week. The food portion of our weekly grocery bill, not including cleaning supplies and toiletries, is about $200 a week. There are just four of us, plus a tiny dog who eats nothing but kibble.

This issue keeps popping up. This week’s “Eat, Drink and Be Healthy” column is about how to feed a 14-year-old boy healthfully, and without breaking the (piggy) bank. And in this week’s “Lean & Fit” newsletter, a reader asks for advice about how an older person (presumably on a fixed income) can follow a vegan diet without spending a lot of money.

Earlier this month the USDA’s Economic Research Service issued a fascinating report about the relationship between the prices of certain kinds of food -- those likely to contribute to obesity versus those likely to work the opposite way -- actually appear to influence childhood obesity in the U.S.

I say it’s “fascinating,” but in fact the findings are just what you’d expect:

“Food prices have small but statistically significant effects on children’s BMI, but not all food prices have the same effect. While the magnitude of the price effects is similar for healthier and less healthy foods, the direction differs. Lower prices for some healthier foods, such as lowfat milk and dark green vegetables, are associated with decreases in children’s BMI. In contrast, lower prices for soda, 100 percent juices, starchy vegetables, and sweet snacks are associated with increases in children’s BMI. These results show that the effect of subsidizing healthy food may be just as large as raising prices of less healthy foods.”

I wish we lived in a society in which no food production had to be subsidized by the federal government and in which tax policy weren’t used to guide consumers’ food choices.

It would be wonderful if, in the free market, people naturally gravitated toward buying the foods that were best for their bodies and away from those that provide few health benefits. Alas, that’s not the way things work. For this week’s “Eat, Drink and Be Healthy” Georgia Orcutt, author of the 2007 book “How to Feed a Teenage Boy,” told me about how she talked with her then-teenage boys about making sound food choices:

“’Your dollar is a vote,” she told them, explaining that she was “not going to vote for those foods” by buying junk. “They got it right away,” she says, and began making their own healthful choices with their allowances.’”

That’s as close to that free-market ideal as we’re likely to get. So, from now on, I’m going to try harder to vote with my food dollars. Which is not to say I won’t occasionally “vote” for a big barrel of UTZ cheese balls, as I did for this weekend’s cookout. How are your food choices affected by the price of food these days? What are your money-saving strategies? And, if you happen to have a 14- year-old boy of your own, how on earth do you keep him full?