Shark Week Returns: What We Can Learn from a Shark's Diet
This is the 25th anniversary of Discovery Channel’s “Shark Week.” The popular show has become a viewing frenzy for fans who have an up-close look at one of the most feared animals in their natural habitat. From the comfort of living rooms, 20+ million viewers peer into the daily lives of sharks. There are more than 400 types of sharks of all sizes and colors. However, when we think of sharks, typically our next thought is what they eat.
Would you be surprised to learn that sharks only eat about 2 percent of their total body weight? While they mostly dine on other fish and marine mammals, sharks have also been known to eat what is available, whether that is crab, clams or even other sharks. The great white shark is by far the head of the food chain, unless a killer whale decides it’s lunch time and a great white is within striking distance. Sharks’ only other enemy is man.
Looking closer at the shark diet, it is interesting to see how their diets differ from humans’ diets. While we mostly operate on three meals a day, sharks can go days, weeks, months and sometimes more than a year without eating. Because sharks are cold blooded, they don’t burn energy as fast as humans do, requiring fewer meals. Also, sharks survive on the oil in their liver that is stored after they eat. When this oil gets low, they know it is time to find their next meal.
Is a shark’s diet good for humans?
Fish provide a good source of lean protein, omega-3 fatty acids and are low in saturated fat. A balanced diet including fish helps promote proper growth and development for children as well as expectant mothers. However, nearly all fish contain some level of mercury. Higher levels of mercury can harm an unborn baby and a child’s developing nervous system. Shark, swordfish, king mackerel and tilefish contain high levels of mercury and should not be eaten by children or pregnant women. Fish and shellfish with low levels of mercury, including salmon, shrimp and canned tuna, are OK to eat up to 12 ounces a week. If you have any questions about incorporating fish into your diet, please ask your physician.
Fish and shellfish should only be a component of a healthy diet for humans. Sharks don’t have access to many fruits or vegetables, which are staples in a healthy human diet. We also require more energy to get through the day, so waiting weeks or months in between meals is not an option for humans.
One tip we can take away from sharks’ eating habits is their ability not to overeat. Although they may not know exactly where their next meal will come from, sharks only eat what they need to eat. Humans can overeat for a number of reasons. From emotional eating to thinking we are hungry when actually we are thirsty, knowing when to stop eating can be a challenge for humans. Perhaps we should skip the buttered popcorn when tuning into “Shark Week” and just enjoy the marvel of these mysterious animals in between meals.