6 Surprising Ways Your Diet Hurts Your Health

An unhealthy diet can do a lot more than pack on the pounds.

Medically reviewed in March 2022

ice cream
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It’s no surprise that the foods we eat can affect our waistlines, but a poor diet that’s high in trans fats, saturated fats and processed foods can do so much more than make us go up a pant size. “It sounds simplistic, but we really are what we eat,” says nutritionist Kathryn Friedman, BS, CHHC, of Lourdes Wellness Services in Collingswood, New Jersey. “What we put in our body is used as building blocks to create new cells. A junky diet affects everything.” Click through to discover the worst food offenders – and what to add to your plate for a healthy diet.

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It Can Age Your Skin

“The signs of aging will show up more pronounced and possibly earlier if you have a lifelong diet that’s not good,” says Friedman. Fried foods, sugar, refined white flower, sodium and alcohol are particularly bad for your complexion, making skin look pale and pasty.  “One reason a plant-based diet is so good for you is that gram for gram, plant foods are loaded with more nutrients than animal foods,” she says. To give your skin a healthy glow, Friedman suggests eating foods rich in vitamins A, C and E, like fruits, veggies, nuts, seeds and olive oil. 

man with stomach pains
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2. It Can Cause Aches and Pains

If you experience stomach pain, frequent headaches or joint pain, it’s possible that a poor diet is blame. “Junk food, processed food and especially the wrong types of fats like butter, cheese and red meat have an inflammatory effect on the body, causing pain and discomfort,” says Friedman. Inflammation also makes conditions like rheumatoid arthritis and inflammatory bowel disease worse. Friedman recommends eating “clean,” which means loading up on vegetables, healthy fats and soluble fiber. “Try it for even a few days and see if you feel better,” she says. 

bowl of rich dark chocolate ice cream
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3. It Can Put You in a Bad Mood

Chocolate ice cream is supposed to put you in a good mood, so how can that creamy, sugary treat translate into a bad one? According to Friedman, it all boils down to blood sugar. Fluctuations in blood sugar can leave you feeling irritable, tired or even depressed. It’s also makes it more difficult to focus and have the resources available to cope well with the stressors of the day. Friedman recommends limiting food with added sugars, not skipping meals and eating lots of green vegetables to help keep blood sugar steady. 

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4. It Can Make You Forgetful

Can’t remember where you left your car keys or the name of someone you just met? Your diet may be to blame. “Your brain needs good nutrition, just like the rest of your body,” says Friedman. A poor diet, she says, can affect your concentration levels and memory. In fact, one study published in the Annals of Neurology found that women who ate foods high in saturated fats, like red meat and butter, did worse on thinking and memory tests than those who ate lower amounts of the bad-for-you fats. To nourish your brain cells, Friedman recommends eating foods rich in omega-3 fatty acids like fish, nuts and flaxseed.

man in bed
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5. It Can Give You a Bad Night’s Sleep

Quality shuteye is essential for your health and well-being, but chances are you’re not getting restful sleep at night if you go heavy on high fat, sugary foods during the day. A diet rich in fried and spicy foods may upset your stomach, further interfering with sleep. And late-night noshing only compounds the problem. “Your body wants to be resting, but instead it’s digesting,” Friedman says.

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6. It Can Damage Your Hair

A diet that’s deficient in certain nutrients can make hair dull, thinning and even fall out. Friedman says that lean protein as well as certain vitamins and minerals like biotin, vitamins A, C and E and B vitamins are especially important for thick, luscious locks.

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Make Slow Changes

The idea that another potato chip or candy bar will never again pass your lips is not practical or sustainable. Friedman suggests that “all or nothing” thinking isn’t the path to healthier eating for the long term. “Just shifting away from one bad food that you eat on a daily basis is an accomplishment and a good goal to set,” she says. “You could slowly start to change how your body responds, how you feel and how your body works during your very next meal. You could start today.”

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