How Donald Trump's McDonald's Obsession Will Ruin His Body

President Donald Trump at a banquet dinner. He notably eats fast food because he deems it to be cleaner. JIM WATSON/AFP/Getty Images

President Donald Trump's diet is notorious and people love to discuss our leader's taste for fast food. Fire and Fury: Inside the Trump White House, a new book written by author Michael Wolff being released on January 5, includes insights about Trump's diet that echo earlier reports and online chatter. What toll might all that fast food be taking on the president's health?

Related: Donald Trump is Right. Fast Food Joints Are Cleaner Than Swanky Restaurants

To recap, Trump likes to eat fast food largely because he thinks it's cleaner and safer, according to Wolff. "He had a longtime fear of being poisoned, one reason why he liked to eat at McDonald's—nobody knew he was coming and the food was safely premade," writes Wolff, in an excerpt published by New York Magazine.

Trump may be right about fast food restaurants being cleaner than other establishments, according to one very small study. But drive-thru meals aren't known for being healthy. How long will it take before a steady diet of high-fat foods harms his body?

It depends, says New York-based registered dietitian Carolina Guizar. She tells Newsweek that many factors determine how a lifetime of Big Macs and fries will impact your body, including genetics and lifestyle factors such as physical activity or smoking.

"I have a grandfather who ate fast food multiple times a week for about 40 years and he's at a normal weight with no evidence of diabetes or heart disease," said Guizar. But she clarifies that he was physically active and also ate plenty of fruits and vegetables.

Eating fast food long-term can be potentially harmful, she emphasizes. "If intake of high fat and high sugar meals is repeated and long-term, I'm talking months and years without compensatory behaviors, you do put yourself at risk for obesity, diabetes and heart disease," she said.

Trump's go-to order at McDonald's includes two Filet-O-Fish sandwiches, two Big Macs and a chocolate shake, according to a story in The Washington Post. The nutritional content of that single meal is higher than dietary recommendations for an entire day, coming in at 2,420 calories, 3,470 mg of sodium, 102 grams of sugar and only 11 grams of fiber, according to the chain's website.

"This is a huge amount of food to consume in one sitting unless you are an athlete," Guizar said, suggesting a Filet-O-Fish, kids fries and small soda as a smarter choice.

Aside from the obvious reasons, like fat and high calorie content, fast food is less than ideal not only because it lacks nutrients but also because it's loaded with chemicals and preservatives, according to Guizar.

In 2016, researchers at George Washington University found that people who ate fast food had higher quantities of chemicals known as phthalates in their systems. Phthalates are found in a range of products from shampoo to raincoats to car plastics. Although the Centers for Disease Control and Prevention states that it's not really known how the substances affect health, studies have shown that they could cause fertility problems in animals.

Research has indicated that fast food harms your brain, too. In a study on children, researchers from Ohio State University found a link between fast food consumption and impaired memory and learning, reported Science Daily in 2014. Another study has linked high-glycemic foods, which dominate fast food menus, to negative moods and decreased cognition.

Guizar said that anecdotally both she and her clients report feeling tired, sluggish and unfocused after consuming these greasy meals. She believes they could hinder mental performance.

"If anyone were to consume the quantity you just stated, they would likely feel the same effects but amplified," she said of Trump's order. "I would not recommend this type of meal regularly for anyone, and especially for someone whose position is high stress and requires clear thinking at all times."

But Guizar doesn't demonize fast food completely. It is possible, she says, to make healthy choices at fast food chains.

Perhaps the president should consider replacing his standard order for a grilled chicken salad.