In a recent study published in the journal Food & Function, researchers have found that blending certain fruits together in a smoothie might not have as many health benefits as previously thought. The study focused specifically on the flavanol content of fruits and found that when fruits high in the enzyme that turns fruit brown when exposed to oxygen, such as bananas, are combined with fruits high in flavanols, like berries, the flavanol content declines rapidly. After just 30 minutes, one flavanol dropped by 80%.
Flavanols are plant compounds that have been shown to boost health and promote cardiometabolic health. However, the study's lead author, Javier Ottaviani, advises against combining flavanol-rich ingredients with fruits that easily turn brown when cut, as it can destroy the flavanol content. This effect also occurs when fruits are pulverized or destroyed, allowing contact between the enzyme and flavanols.
Despite these findings, experts suggest that individuals should not give up on smoothies altogether. Mary Ann Lila, director of the Plants for Human Health Institute, states that a smoothie is still a healthy way to consume bioactive compounds in fruit, as long as it is consumed immediately and not left to turn brown. Ottaviani also notes that most people do not need to specifically boost their flavanol intake through smoothies, as a varied diet with sources like tea can make up for any loss in flavanol content from bananas.
However, it is important to be mindful of the total amount of calories and sugar in a smoothie, as too much fruit can lead to overconsumption. Adding protein to a smoothie can help increase satiety and make it a more balanced meal replacement. Store-bought smoothies may also contain added sugar and processed additives that can impair the nutrient content.
To create a nutritious and delicious smoothie, experts recommend including a mix of nutrients such as berries, spinach, Greek yogurt or protein powder, and a fiber and fat source. Adding vegetables like avocado or kale can increase bioactive compounds while reducing sugar content. Additional protein sources can include kefir, cottage cheese, tofu, nut butter, or seeds. To enhance flavor, ingredients like honey, spices, cocoa powder, or ginger can be added.
In conclusion, while combining certain fruits in smoothies may reduce flavanol content, a balanced and mindful approach to smoothie consumption can still provide health benefits. It is important to focus on overall dietary diversity and moderation to maintain a healthy lifestyle.