Two drinks dietitians recommend for constipation relief

If you want to prevent constipation or ease its symptoms using natural foods, consider smoothies made with prunes and kiwis. They can be prepared easily at home without the side-effect concerns associated with laxatives or probiotic supplements — and they deliver additional nutrients from the fruit itself.

Prunes and kiwis are among the gut-health foods dietitians most frequently recommend. Kim Min-jung, a US-registered dietitian, said three elements are essential for healthy bowel habits: adequate hydration, sufficient dietary fiber intake, and an environment in which beneficial gut bacteria can thrive.

She went on to say that "the dietary fiber abundant in prunes and kiwis serves as food (prebiotics) that beneficial gut bacteria use for energy," adding that it "can help maintain a healthy gut environment and regular bowel activity." In the body, dietary fiber reaches the large intestine, where beneficial bacteria break it down and ferment itto obtain the energy they need to grow — a process that also produces metabolites beneficial to gut health.

Kim said blending prunes and kiwis with plain yogurt, milk or almond milk into a smoothie is a tasty way to boost both fiber and hydration, and that the probiotics in yogurt and the prebiotics in prunes work together synergistically.

Prunes are particularly notable for their high fiber content. According to the US Department of Agriculture, prunes contain 7 grams of dietary fiber per 100 grams — roughly three to four times more than apples, bananas or tangerines.

Multiple research papers have confirmed the digestive health benefits of prunes. A study published in Clinical Nutrition in 2019 found that when 120 healthy adults consumed prunes daily for three weeks, both stool volume and bowel movement frequency increased. Levels of beneficial gut bacteria also rose.

A representative of the California Prune Board said prunes are great eaten on their own but also make an excellent smoothie ingredient, and shared a homemade recipe called the "Prune Purple Power Smoothie" — a blend that combines prunes with other purple foods.

To make it, blend chopped prunes, spinach, plain Greek yogurt, pomegranate juice, frozen berries such as blueberries, and honey. Add ice until the desired consistency is reached.

Kiwis are also high in dietary fiber and contain a compound called raphides. Researchers at the Nottingham Biomedical Research Centre, part of the UK's National Institute for Health Research, published a study in Alimentary Pharmacology & Therapeutics in 2019 finding that the dietary fiber and digestive enzyme actinidin in kiwis improve the gut's mucus layer and intestinal environment, helping stool pass more smoothly.

To make a kiwi smoothie, wash two ripe green kiwis, then blend them with almond milk or soy milk and spinach. Add ice to finish.

Frozen pineapple can be added for extra sweetness. The most popular pairing for kiwi is banana, which adds a gentle sweetness and creamy texture. Place two kiwis and one banana in a blender, then add milk or almond milk, plain Greek yogurt and ice, and blend until smooth.