Collagen. Whether you vaguely remember learning about the protein in biology class or you can’t scroll down your Instagram feed without seeing a colorful collagen smoothie bowl recipe, you probably know that it’s a vital building block for our bodies.

“Collagen is what provides structure for our body,” says Erin Skinner, M.S., R.D.N, L.D.N, author of The Bone Broth Miracle Diet. “It keeps skin looking youthful, joints healthy, and our gut in great shape.”

Unfortunately, our natural collagen-producing abilities decrease with age, which is why it’s extra important to support healthy collagen synthesis as we age, says Diana Gariglio-Clelland, R.D., a consulting dietitian for Next Luxury. We can do this by eating collagen-boosting foods and through supplementation.

Still, there are some seemingly innocent things we do (or don’t do!) that can mess with our collagen production. Here are five collagen killers to look out for—plus how to remedy them.

1. You don’t consume enough antioxidants

Bring on the berries and the spinach, folks. “Antioxidants help protect cells from damage, as well as reduce the breakdown of collagen,” says Gariglio-Clelland. “Vitamins C and E, as well as carotenoids from orange-colored produce, are some of the most effective antioxidants related to collagen production.” 

“Getting the full antioxidant benefits of plants requires eating a large variety of different colored fruits and vegetables,” Skinner adds. “Unfortunately, most Americans eat too few plants and too little variety.” To get enough of these antioxidants, strive to incorporate foods like citrus fruits, bell peppers, strawberries, broccoli, nuts, seeds, pumpkin, carrots, and spinach into your diet regularly.

In total, you want to hit at least four cups of cooked vegetables per day—ideally incorporating red, yellow, purple/blue, green, and beige/white produce. 

For bonus points: “Shoot for options that are brightly colored throughout (like berries) rather than just in the skin (like an apple),” Skinner adds.

2. You spend too much time in the sun 

You’ve heard it before, but the phrase “too much of a good thing” definitely applies to the sun. “Excessive sun exposure can lead to premature aging (wrinkles and dry skin),” explains Lauren Minchen, M.P.H., R.D.N., C.D.N., nutrition consultant for AI-driven diet diary app Freshbit. “The UVA and UVB rays from the sun actively break down collagen in the skin.”

Your best bet for keeping the collagen in your skin healthy? “Limiting time in the midday sunlight and applying sunscreen daily can help reduce collagen loss from sun exposure,” Minchen says. Don’t forget to reapply that SPF throughout the day! 

3. You follow a low-carb or low-glycemic diet 

While low-carb or low-glycemic diets can be balanced and nutritious, they may impact collagen creation. “Aside from amino acids, vitamin C is also critical for collagen production.  However, the popularity of low-carbohydrate diets has many people passing on the oranges and papayas,” says Skinner. “If you’re eating low-carb or low-glycemic, make sure that you’re getting enough vitamin C from lower-carb foods like berries, peppers, and tomatoes.” 

Read More: 6 Carbs That Can Help You Lose Weight

FYI: If you’re a smoker or a pregnant or breastfeeding woman, you need more vitamin C than the typical recommended amount, which is 90 milligrams per day for men and 75 for women. Not sure if you’re getting enough? Skinner recommends tracking your vitamin and mineral intake using a free tracker like Cronometer.com.  

4. You Fall Short On high-quality protein  

Back to the biology basics: Collagen protein is made up of amino acids linked together in what’s called a collagen helix. 

“Of the 20 different amino acids, your body can produce just 11 on its own,” explains Gariglio-Clelland. “The other nine amino acids, called essential amino acids, must be obtained through the diet.” 

To best support your body’s ability to efficiently produce proteins like collagen, Gariglio-Clelland recommends ensuring you’re consuming ample essential amino acids by emphasizing complete proteins (which contain all nine essential amino acids)—such as meat, poultry, eggs, fish, dairy, quinoa and soybeans—whenever possible.

You can also combine certain incomplete proteins (rice and beans are a great example) to create a meal that ultimately offers all of the essential amino acids to ensure you get your fill.

5. You don’t drink enough water

Do you find yourself sipping on coffee and cola more often than good old fashioned water throughout the day? Time to change that.

“Water is an essential part of the collagen matrix, and without it, collagen can actually dry up,” says Minchen. “Dehydration can lead to decreased collagen production and a poor integrity of the collagen we already have in our tissues.” The results of shortening collagen molecules: dry, sagging skin, joint pain, and hair loss.

Read More: 8 Fun Ways To Drink More Water If You Hate Water

Minchen recommends drinking at least two liters of water per day, noting that those who drink caffeine and/or exercise may need even more. If guzzling H2O isn’t your typical M.O., check out eight fun ways to drink more water if you hate water.