Constipation is an uncomfortable condition, and you may be able to prevent it or relieve symptoms by modifying your diet. Smoothies with fruit, yogurt or other healthy ingredients can provide nutrients to promote laxation, and you can eat them for breakfast or during the day. Talk to your doctor if you have constipation or other health concerns.

Dietary Fiber

Dietary fiber has a laxative effect. Make your smoothie with high-fiber fruits, such as raspberries, peaches, guava, blackberries or bananas, which all have at least 3 grams dietary fiber per serving. The recommended amount of fiber is at least 14 grams dietary fiber for each 1,000 calories that you eat, according to the 2010 Dietary Guidelines from the U.S. Department of Health and Human Services. Fiber increases the bulk of your stool so that it is easier to pass.

Hydration

A smoothie can prevent or relieve constipation because it helps keep you hydrated, and dehydration can make constipation worse. Water may have a laxative effect as well because it makes stools softer and less painful. Smoothies provide fluid from ice and from fruit, fruit juice, yogurt or milk. You need at least 72 to 100 ounces of fluid per day, and more if you exercise frequently or live in hot or humid conditions, according to the University of Michigan.

Powdered Ingredients

Wheat bran, wheat flakes, oat bran and flaxseed meal can provide additional dietary fiber to your smoothie, and they have laxative effects. Psyllium, or isolated fiber from psyllium husk, is available as a powdered fiber supplement, and it is a common laxative that you can add to smoothies. Psyllium also may lower your cholesterol levels, but you should only take it if your doctor approves.

Other Information

Yogurt with live and active cultures contributes probiotics, which are healthy bacteria that live in your gut and promote bowel regularity. Along with probiotics, your smoothie can provide prebiotics, or fibers which support the growth of probiotics, if you add ingredients such as flaxseed, bananas, berries and honey. Eat an overall balanced diet, and consult your doctor if you are having trouble with your digestive health.