Smoothies: Nutrients, What Research Shows and Safety

A smoothie is a drink made by blending whole fruit, and sometimes vegetables, yogurt, milk, ice or juice, into one thick drink. Unlike juice, blending can keep some fiber in the glass [6], but the NHS notes that crushing fruit releases its sugars [3], and a drink is easy to finish quickly. There is no standard smoothie, so this page uses two USDA entries as examples and says plainly what the research does and does not show. It keeps smoothies apart from juice cleanses, powders and supplements.

Read this first

• Smoothies vary hugely. USDA lists two very different ones: a bottled fruit juice smoothie (mango) and a fast-food strawberry-banana smoothie made with ice and low-fat yogurt. [1] [2] Each has about 12.5 g of sugars per 100 g, which is about 30 g in 8 fluid ounces and 44 g in 12. [1] [2]
• The NHS counts smoothies with juice, not as extra fruit. It lets unsweetened juice and smoothies together count as at most one portion of 5 A DAY, up to 150 ml a day, because crushing fruit releases sugars that can damage teeth. [3]
• Food safety: the FDA says outbreaks have been linked to smoothies made with unpasteurized juice. [8] A 2023 US hepatitis A outbreak was linked to frozen strawberries. [10] Pregnant women should avoid unpasteurized juice. [8]
• Blending is not clearly worse for blood sugar than eating the fruit whole in the small studies we read, but those were in healthy people. [5] [6]
• Medicines: if you add leafy greens and take warfarin, keep vitamin K steady. [13]
• Emergency: smoothies can contain milk, yogurt, nut butters, seeds or protein powders. For trouble breathing or swelling of the face or throat after any food, call 911 (or your local emergency number).

What is in it (USDA values)

USDA lists two smoothie items (SR Legacy). Both are per 100 g, with the USDA household portion shown. They are different products, so do not read them as one "average" smoothie. [1] [2] A dash means USDA lists no value.

% Daily Value uses the FDA 2016 Daily Values; values vary with recipe, fruit, size and brand. The serving figures are the 100 g values multiplied by 2.4 and 3.47. USDA lists no caffeine and no alcohol for either item. [1] [2] The fiber difference shows why the recipe matters: the bottled juice smoothie lists 0 g of fiber, while the yogurt smoothie lists 0.9 g per 100 g. [1] [2] USDA does not say how much of the sugar was added, so we cannot tell added from natural sugars. We did not read a source that measured plant compounds in these products, so we make no antioxidant claim.

What research says

We did not check who funded the glucose and fullness studies, so we say nothing about it.

Eaten as food vs taken as juice or supplement. The studies above used whole-fruit drinks. Smoothies made with protein powders, supplements or juice concentrates are different products, and we did not read trials on them. A smoothie made mostly from juice (like the bottled mango example) is closer to juice than to blended whole fruit. [1] See Fruit juice vs whole fruit.

How much is a normal serving

USDA's household portions are 8 fluid ounces (240 g) for the bottled mango smoothie and 12 fluid ounces (347 g) for the strawberry-banana one. [1] [2] That is information, not a prescription. The NHS counts unsweetened juice and smoothies together as at most one portion of 5 A DAY and advises 150 ml a day. [3] WHO recommends keeping free sugars, which include sugars in fruit juices, under 10% of daily energy. [4] The 2020-2025 Dietary Guidelines for Americans say fruit choices should be "especially whole fruit." [15] For children, the American Academy of Pediatrics (2017) advises no juice in the first year and at most 4 oz a day at ages 1 to 3, and prefers whole fruit; it does not give a separate figure for smoothies in the page we read. [11]

Safety, allergy and medicines

• Sugar and calories: the two USDA smoothies list 30 g and 44 g of sugars per serving. [1] [2] The NHS says even unsweetened smoothies are sugary and suggests having them with meals rather than between meals to protect teeth. [3]
• Unpasteurized juice: the FDA says outbreaks have been tied to smoothies made with unpasteurized juice, and that pasteurized juice is safe. Confirm the juice is pasteurized and wash fresh fruit. [8] The FDA says untreated juice must carry a warning label, and that children, older adults, pregnant women and people with weakened immune systems can become seriously ill from it. [9]
• Frozen berries: the FDA and CDC investigated hepatitis A illnesses (10 cases, 4 hospitalizations) linked to recalled frozen strawberries in 2023; the advice was not to eat recalled product, and to talk to a clinician about post-exposure vaccination within 14 days if you ate it. [10] The page we read did not say whether freezing kills the virus.
• Washing produce: the FDA says rinse produce under running water without soap, scrub with a brush, and cut away damaged areas; avoid raw sprouts of any kind in pregnancy. [8]
• Pregnancy and breastfeeding: pregnant women should avoid unpasteurized juice. [8] We did not read a source on other smoothie ingredients in pregnancy.
• Warfarin: kale, spinach and other leafy greens are rich in vitamin K, and sudden changes can change the effect of warfarin. [13] Keep greens steady and tell your prescriber. See Foods and medicine interactions.
• Kidney disease and potassium: USDA lists 455 mg of potassium in the 12 fl oz strawberry-banana smoothie. [2] The National Kidney Foundation says people with kidney disease may be advised to limit high-potassium foods; bananas and other ingredients vary. [14]
• Diabetes: the sugar content is high, and we did not find a trial in people with diabetes. Ask a clinician or dietitian.
• Allergy: smoothies often include milk, yogurt, nuts, seeds or protein powders. Read the ingredient list; for trouble breathing or swelling of the face or throat, call 911. See Food allergy basics and emergency signs.
• Children: the AAP says unpasteurized juice should be strongly discouraged for children of all ages. [11]

Choosing, storing and food safety

• Ask whether any juice in a smoothie bar's recipe is pasteurized. [8]
• At home, wash fruit and your hands (at least 20 seconds), and keep ingredients cold. [9]
• We did not read a source on how long a blended smoothie keeps; drink it soon after making it.

Related pages

• Fruit juice vs whole fruit
• Detox foods and juice cleanse claims
• Pasteurized vs unpasteurized foods
• Foods for blood sugar control
• Green and vegetable juices
• Foods in pregnancy: what official bodies advise