Why Matt Damon’s Teeth Looked So Bad in The Martian (Spoiler Alert!)Oct 09, 2015, by
In The Martian, Matt Damon plays astronaut/botanist Mark Watney, who is stranded on the planet Mars and is forced to try to survive for more than 600 days on his own. At the end of his ordeal, Matt Damon looks like he’s been through some kind of Hell. He’s bruised and covered in sores, and his teeth are terrible, too. They are blackened in places, elongated, and his gums are red and swollen. It’s hard to know whether this is an accurate representation of what a man’s teeth would look like after what he went through, but it is at least a gesture to the myriad problems an astronaut would face in this situation.
There are three major challenges that confront Mark Watney’s teeth during his time on Mars: nutrition, hygiene, and lack of gravity.
Nutrition and Your Teeth
Mark Watney survives on Mars by eating potatoes for most of his voyage. Potatoes aren’t the worst choice for a single food if you have to choose just one, but they’re not ideal. On the plus side, potatoes have a lot of vitamin C, so that eating the 1500 Calories of potatoes he plans on at one point would give him 700% of his recommended vitamin C, so the space pirate, unlike your nautical pirate, wouldn’t get scurvy.
But there are other problems. Our teeth depend on other nutrients, such as vitamin A, vitamin D, and calcium. Potatoes have virtually no vitamin A or vitamin D. While on Earth a person could make their own vitamin D–all it takes is exposing skin to sun–he can’t do that on Mars. Even if he could expose his skin to the sun on Mars, it would take hours a day, possibly longer than the daylight hours he had available. If we assume that NASA lighting allowed him to make vitamin D, he’d be a little better off.
But the whole reason why we need vitamin D is so our body can use calcium, and he’d be very short on that. At best, his potato diet would yield him about 20% of the calcium he needed, so his teeth would gradually suffer from a calcium deficiency, unable to replenish mineral content lost to decay.
And with a vitamin A deficiency, it’s no wonder that Watney’s gums looked terrible.
In the book, author Andy Weir gets around this problem by claiming that Watney had access to enough multivitamins to last for years. This is a dubious caveat, at best, and it’s just as well the movie didn’t opt to go there.
By the end of the movie it seems like Watney isn’t taking much time on any part of his hygiene routine. Based on the comments of his fellow astronauts, Watney has definitely missed a few showers, and it’s likely he missed a lot of toothbrushing, too. If we assume that the Ares III mission was supplied with oral hygiene equipment comparable to their food supply, Watney would have run out of toothpaste on Sol 400 (a Sol is a day on Mars, about 24.5 hours). Since he didn’t get picked up until Sol 549, that’s about 150 days (5 months) without oral hygiene supplies.
During this time, he’s also suffering malnutrition and eating a high-starch diet, which is going to put his oral bacteria into overdrive. As they attack his teeth and gums, his condition will be even worse because he won’t have seen a dentist or hygienist during the nearly two years he was on Mars. During the early part of this time, when he was eating a reasonable diet and had good minerals, he would have experienced a buildup of tartar, which would shelter oral bacteria and allow them to attack his teeth and gums even more vigorously. Tartar removal is one of the main reasons to make your regular checkups and cleaning visits.
Throughout the movie, all the astronauts are experiencing low gravity. On Mars, the surface gravity is about 0.37 what it is on Earth (g). On the Hermes, most of the time astronauts are in microgravity (essentially no gravity), and even in the rotating section of the ship, astronauts only get 0.4 (g). This means that their bodies would probably begin removing bone from around their teeth, which would put their teeth at risk. Even with the Martian gravity and the simulated gravity, it’s likely that multiple teeth would be lost, especially Watney’s teeth, with the additional stresses they are put under.
So it makes sense that they made Damon’s teeth look so bad at the end of the movie. If anything, they were too light on him–the odds are good that he would have lost more teeth.
But it is realistic that by the end of the movie he should have a bright white set of teeth again. Reconstructive dentistry can handle virtually any challenge.