Reference
Sanguigni V, Manco M, Sorge R, Gnessi L, Francomano D. Natural antioxidant ice cream acutely reduces oxidative stress and improves vascular function and physical performance in healthy individuals. Nutrition. 2017;33:225-233.
Design
This was a controlled, single-blind, crossover study. Three days before beginning the study, all participants underwent an exercise stress test. They were then randomly allocated to a treatment sequence with 100 g of either an experimental high antioxidant ice cream or a standard milk chocolate ice cream (control). There was a 1-week washout between the 2 phases of the study.
Participants
Fourteen healthy, nonsmoking volunteers (7 men and 7 women) aged 20 to 40 years
Study Medication and Dosage
The control ice cream consisted of unsweetened milk chocolate ice cream. The antioxidant ice cream was made from a combination of milk solids, ground hazelnuts, and cocoa with added green tea extract. Both ice creams were relatively low-fat (about 9%) but the experimental mix was lower in saturated fat (1.4% vs 6%). The experimental ice cream contained 1,817 mg/L polyphenols while the control product contained less than 100 mg; the organoleptic characteristics of the 2 products were similar.
Outcome Measures
Markers of oxidative stress via plasma hydroperoxides (ROOHs) and H2O2, serum antioxidant status (ferric reducing antioxidant power [FRAP]), nitric oxide (NO) bioavailability, and endothelial tonometry through endothelium flow-mediated vasodilation (FMD) were evaluated in fasting condition at baseline (time 0) and 2 hours after the ingestion of the antioxidant or control ice creams. The exercise stress test was performed before randomization and 2 hours after each ice cream meal test. In both experiments, the ice cream was eaten in 10 minutes or less.
Key Findings
Two hours after the participants ate the high antioxidant ice cream, their blood levels of polyphenols increased significantly (P<0.001) and oxidative stress decreased significantly. Available antioxidant capacity and NO bioavailability both improved significantly. Both measures of endothelium-mediated artery dilation also improved significantly. Exercise performance significantly improved after eating the antioxidant version of the ice cream vs after eating the control ice cream.
Practice Implications
This is the first study we know of to show that, with a little intelligent tinkering, ice cream might be modified to improve vascular function and physical performance simply by increasing polyphenols to reduce oxidative stress. In other words, good-for-you ice cream can be, and it can still taste good. Technically we should probably call this stuff a frozen confection rather than ice cream as it did not in fact contain cream.
The problem with ice cream may not be that it is calorically dense but that it is so polyphenol-light.
We know that diets high in fruits and vegetables are protective against heart disease, cancer, and diabetes. These benefits result from the higher polyphenol content provided by these foods; polyphenols stimulate powerful antioxidant action in the body. In separate reviews both Arts (2005) and Hooper (2008) concluded that there is an inverse association between high dietary polyphenol intake and cardiovascular disease (CVD), with high polyphenol diets reducing CVD mortality by 65%.1,2
Figuring out what people should eat and getting them to do so are 2 very different challenges. The natural inclination of most humans is to choose calorically dense, highly processed, low polyphenol foods—what we commonly call junk food. Efforts to educate the public to make healthy food choices have met with very limited success. Thus attention is shifting to whether food formulations may be modified to make healthier versions of unhealthy foods.
This healthy version of chocolate ice cream was created by reducing saturated fats, replacing milk fat with ground hazelnuts, and increasing the polyphenols through addition of cocoa solids and green tea extracts.
Moderate chocolate consumption is associated with reduced CVD in men and women. This protective benefit disappears at high consumption levels—chocolate consumers who eat chocolate every day have a higher CVD risk than nonconsumers.3,4 The caffeine, theobromine, and fat in chocolate are generally blamed for this biphasic response, though it is unclear what specifically is responsible.5
The inflammatory action of ice cream has been attributed to its high fat content, but results of a 2010 study suggest otherwise. In this study, investigators gave low-fat ice cream to obese participants and tracked markers of inflammation and metabolic syndrome. They found no benefit to low-fat substitution.6 A 2012 trial also failed to show that full-fat dairy foods increased biomarkers related to inflammation or atherogenesis.7
A 2013 meta-analysis that compared whole-fat and low-fat dairy food consumption noted that consumption of high-fat dairy foods was associated with some weight gain but had only minor effects on other cardiometabolic risk factors,8 making it appear that the historic focus on low-fat dairy products was less useful than we hoped. According to a separate 2013 study, fermented full-fat dairy products were no worse than low-fat dairy, and in some ways were a better choice.9 Thus one must wonder whether the substitution of nut fats for dairy fat in this current chocolate ice cream study was altogether necessary for the improved CVD markers. Perhaps simply using fermented whole milk products might have been adequate.
The problem with ice cream may not be that it is calorically dense but that it is so polyphenol-light. If polyphenol levels are increased so that they balance the calories, foods that we traditionally think of as unhealthy may no longer be detrimental.10
Other strategies are being tested to turn ice cream into health food. One idea that is growing is the addition of probiotics—in particular bacteria that have been enriched with magnesium.11 Another angle is to add prebiotic or synbiotic fiber to the ice cream along with probiotics.12
While there seem to be multiple ways to turn junk food into health food, product development and retail availability appear to be lagging behind. We would wish those in food product development might translate these ideas into consumer products with a bit more speed and enthusiasm.
Obviously current government regulations that insist on specific, defined ingredients and specific ratios of those ingredients in specific foods may be seen as a hindrance to new product development. Ice cream is so tightly defined in terms of what it contains that label ingredient lists are optional. It would be unlikely for the chocolate hazelnut concoction used in this study to ever make it to a freezer case in the United States in a package labeled ice cream.
We have known for years that chocolate polyphenols are responsible for chocolate’s CVD benefit, but we have yet to see any of the “healthy” chocolates actually label their packages with polyphenol content. Is this a result of government labeling rules or company intransigence? Until the labels specify polyphenol content, consumers will find it challenging to discern which products have the most benefit. While we may not know the ideal daily polyphenol intake, it would still be nice to know how much is in our various foods and be able to compare products available for purchase.
