What Vegetables and Fruits Should Not Be Juiced?

People who drink juice have better quality diets than people who don't. Carrot tops and rhubarb leaves should not be juiced because they are toxic and you shouldn't juice citrus peels because they can upset your stomach.

People who drink juice have better quality diets than people who don't. Juice provides a concentrated source of the vitamins, minerals, and phytonutrients found in fruits and vegetables. Phytonutrients are beneficial compounds found in plants that may help improve health and fight diseases. However, there are certain fruits and vegetables that shouldn't be juiced or should only be juiced in moderation. 

There are some parts of certain fruits and vegetables that you shouldn't juice. 

Apples can be juiced freely, but you shouldn't include the seeds in your juice. Apple seeds contain amygdalin, which is a type of cyanogenic glycoside. Cyanogenic glycosides contain cyanide and sugar. When you digest the sugar, small amounts of cyanide are released. 

Plum and peach pits also contain cyanogenic glycosides, but they aren't likely to be juiced. Apple seeds have lower levels than plums and peaches, but they could still cause a stomachache or food poisoning in an adult. If a small child ingests apple seeds, they could be poisoned. 

Additionally, you shouldn't juice the following plant parts: 

• Carrot tops because they're toxic
• Rhubarb leaves because they're toxic
• The peels of oranges, grapefruit, tangerines, and tangelos because they can upset your stomach

Fruits that have a low water content will be difficult to juice and won't produce much juice. Fruits that have a low water content include: 

• Avocados
• Bananas
• Coconuts
• Any dried fruits or vegetables

Oxalic acid, which is also called oxalate, is a naturally occurring compound in many fruits and vegetables. Oxalates can combine with minerals in your body to form compounds. These compounds are normally excreted in your stool or urine. For people who are prone to developing a certain kind of kidney stones, a diet high in oxalates may contribute to forming kidney stones. 

Additionally, oxalate is toxic to your kidneys in high amounts. Since juicing concentrates the substances in fruits and vegetables, juicing high oxalate foods will result in more oxalate in your body. If you take in large amounts of oxalate, it will have to go through your kidneys to be excreted. This problem can be worse if you're also taking high doses of vitamin C. 

People who have chronic kidney disease or a tendency to develop calcium oxalate kidney stones should avoid juicing foods high in oxalates such as: 

• Spinach
• Beets
• Rhubarb
• Nuts and nut butter

One of the most important steps in preparing healthy juice is making sure your fruit and vegetables are clean and free from foodborne pathogens such as salmonella, listeria, or E. coli. Clean your produce thoroughly to make sure it doesn't contain any bacteria, pesticides, or dirt. 

Here are some tips for making sure your juice doesn't get contaminated: 

Keep your hands clean

Wash your hands with soap and warm water for at least 20 seconds both before and after you handle food. 

Cull your produce

Carefully examine your fruits and vegetables before you juice them. Cut away any bruised or damaged parts. If any of your produce looks rotten, throw it away or compost it. 

Wash and dry your produce

Use running water to wash all of your produce, including fruits and vegetables you grew yourself or bought from a farmers' market or grocery store. If you're washing firm produce, such as cucumbers or melons, scrub it with a produce brush under running water. Do this even if you don't plan to use the peel in your juice. Cleaning the skin will prevent pathogens from being transferred from the skin to the flesh when you're cutting it. 

Don't batch-wash your produce or set it down in a sink because that may increase the risk of cross-contamination. 

After you wash your produce, use a clean cloth or paper towel to dry it. Drying your fruits and vegetables will help further reduce exposure to bacteria. 

For vegetables that are difficult to clean, such as cruciferous vegetables like broccoli, cauliflower, and Brussels sprouts, first blanch them by dunking them in boiling water for 10 seconds. Cruciferous vegetables have tight florets that can harbor bacteria and be difficult to clean. 

Wash green, leafy vegetables by soaking them in a clean bowl of cool water and 1/2 cup of vinegar for 5 to 10 minutes. Swirl them around to help get rid of dirt and insects. After removing them from the vinegar solution, rinse them thoroughly in a colander under running water. Store leafy greens at 40 degrees F or cooler to slow pathogen growth. 

Regardless of what type of juice you consume, you shouldn't make it the primary component of your diet. Juicing can be part of a healthy diet, but you shouldn't drink more than 3/4 to 1 cup of juice daily. Juice doesn't provide the fiber found in whole fruits and vegetables, and it is a concentrated source of calories and sugar. 

If you want to drink your fruits and vegetables, smoothies can be a great alternative to juice. Blending fruits and vegetables retains all of the fiber and provides a more filling drink.