Nutrition Calculator

How the nutrition calculator works

For each ingredient and weight you choose, the calculator adds up typical values from standard reference data, the kind published in the USDA FoodData Central database. The totals it gives you are estimates. Real values shift with the variety and ripeness of the fruit, the brand of yogurt, milk or protein powder, and how carefully the ingredients were measured. With packaged ingredients, the nutrition label on the product is more accurate than any general database can be.

Reading the results

• Calories: the energy in the drink. A smoothie meant as a meal is naturally higher than one meant as a snack.
• Protein: helps with fullness and muscle repair. Greek yogurt, milk, soy milk, tofu and protein powders raise it most.
• Carbohydrate and sugar: mostly from fruit, milk and any sweetener. Blended fruit counts as whole fruit for fiber, but sugars released from blended or juiced fruit are treated as free sugars by the NHS and WHO.
• Fiber: from fruit, vegetables, oats, chia and flax. Most adults in the US and UK eat less than recommended.
• Fat: from nut butter, seeds, avocado and full-fat dairy. Mostly unsaturated in plant sources.

Sugar guidance

The Dietary Guidelines for Americans recommend keeping added sugars below 10 percent of daily calories for everyone aged 2 and older. The NHS advises limiting fruit juice and smoothies to a combined 150ml a day, which counts as a maximum of one of your 5 A Day, because blending releases sugars that can harm teeth. A smoothie built with vegetables, protein and only a portion or two of fruit is easier to keep within these limits.

Weighing makes the difference

A scoop or a handful varies a great deal from one person to the next. A kitchen scale gives you far more accurate numbers, especially for calorie-dense ingredients like nut butters, seeds, avocado and protein powder.

Micronutrients

Leafy greens add vitamin K, folate and other micronutrients. If you take warfarin or another blood thinner, talk to your doctor before you make large changes to how many leafy greens you eat, because vitamin K affects the way these medicines work.

Allergies

Read the labels on milks, yogurts and powders, and check them for allergens such as milk, soy, tree nuts and peanuts.

A worked example

Take a smoothie made with 30g of spinach, 120g of banana, 100g of blueberries, 240g of unsweetened almond milk and 120g of plain Greek yogurt. Most of the carbohydrate and natural sugar comes from the fruit. The yogurt supplies most of the protein. The spinach adds very few calories, but it contributes vitamin K, folate and some fiber. Swap the almond milk for dairy or soy milk and the protein goes up noticeably. Add 15g of chia seeds and you get more fiber and some fat. The quickest way to learn which ingredients move which numbers is to change one ingredient at a time and then recalculate.

Custom ingredients

If an ingredient is not in the quick-add list, use the custom option and enter values from the product's nutrition label, scaled to the weight you use. Labels usually list values per 100g or per serving, so check which before entering numbers. For fresh produce without a label, USDA FoodData Central lets you search for a specific food and see values per 100g.

Numbers are rounded, so a total may differ slightly from the sum of the individual ingredients. If you are on a medically supervised diet, use the figures your dietitian gives you, since they will take into account your specific needs and the exact products you buy.

Sources: USDA FoodData Central; Dietary Guidelines for Americans 2020-2025; NHS: Sugar, the facts; MedlinePlus: Vitamin K and warfarin.