Flickr/Calgary Reviews

Don’t like salads? Get used to being constipated. All the time.

When I was in my early 20s, my diet was… problematic. I worked the night shift at a bakery for minimum wage, and most of what I ate was the cut-off ends of shortbread cookies — which had been thrown in a huge plastic bucket at the end of the day — supplemented with an occasional pizza pocket from the gas station across the street.

My young and relatively unsullied body could survive on that, but it wasn’t pretty. I was a greasy, insomniac mess with the muscle tone of a beached jellyfish.

Thankfully, I grew up and learned to eat right. But some people never do. In fact, most people don’t — the average American consumes almost 500 calories more than they should, each and every day.

And most of those calories aren’t vegetables. A 2013 Center for Disease Control survey revealed the fact that a paltry 8.9% of Americans are meeting their recommended daily allowance of veggies. That’s two and a half cups a day for adult women, and three for men.

I eat a lot of vegetables because I snack while I work, and chomping on snap peas, carrots and baby tomatoes keeps my hands out of the chip bag. But there are lots of reasons why most people don’t.

First, a wide selection of fresh vegetables isn’t available to many Americans. Some live in urban food deserts where grocery shopping is done at corner stores and bodegas that prioritize shelf-stable food that won’t go bad in a matter of days. Others live in remote areas of the heartland where demand isn’t high, so options are limited.

If you think of food price on the basis of how many calories you’re getting for your dollar, veggies are horribly inefficient. Processed foods packed with fats and sugars deliver a more potent energy payload than vegetables do, and we’ve evolved to instinctively prefer that.

The human brain is wired to seek out caloric loads, because in the past food was scarce. Just a few hundred years ago, we had to work for each meal. Now, for most people in the Western world, calories are plentiful and affordable. But we haven’t evolved physically to keep up with that surplus, and it’s making us obese.

The American palate has also been trained with artificially sweet and salty foods to crave a flavor profile that unprocessed vegetables just don’t provide. While bell peppers are sweet and celery is salty, the intense punch of heavily seasoned snack food is orders of magnitude greater.

Finally, there just might not be enough vegetables to go around. Of the vegetables sold in the United States every day, nearly half of them are potatoes and tomatoes. A significant portion of those find themselves processed into French fries, ketchup and pizza sauce. If every American started consuming three cups of leafy greens, squashes and the like a day, farm production would have to jump 70% overnight. And that’s not likely to happen.

So what would happen if you went cold tofurkey and cut out vegetables entirely?

The first thing you’ll miss — and the one that will be most noticeable if you stop — is fiber. The natural, indigestible fiber present in vegetables is an important helper for your stomach and intestines. As the nutrients get broken down, that fiber remains and helps sweep out toxins and other remnants in your system. Without it, you’re likely to suffer from constipation and an increased risk of colorectal cancer.

Aside from the fiber, vegetables pack a potent punch of vitamins, minerals and micronutrients that you’re not going to get anywhere else. Not consuming these nutrients opens your body up for all kinds of diseases. Scurvy, which was the plague of pirates in olden times, is caused by a lack of vitamin C and will make you weak and tired until your teeth fall out. Lack of vitamin A will make your skin dry and your night vision weaker. Not enough vitamin D makes your bones soft and weak. Without vitamin K your blood won’t clot. The list just goes on and on.

Things only get worse the longer you skip your vegetables. Those micronutrients we talked about include potent antioxidants that prevent cell degradation and cancer. And there’s really no other way to get them outside of plant matter.

So to answer that headline question, if you want to survive to a ripe old age, make sure to eat your ripe vegetables.