Daily Added Sugar Limit Calculator (WHO / AHA Guidelines)
**Added sugars** (or **free sugars** in WHO terminology) are sugars added during food processing or cooking — sucrose, high-fructose corn syrup, honey, fruit-juice concentrate — and they exclude the naturally-occurring sugars in whole fruit and milk. Both the WHO (2015) and the American Heart Association (2018) state explicitly that excess added-sugar intake *independently* raises the risk of dental caries, overweight, type-2 diabetes and cardiovascular disease, distinct from other calorie sources. Enter your daily energy intake (typical adults: women 1 800–2 200 kcal, men 2 200–2 800 kcal) and pick one of the published guidelines: (a) **WHO strong** (< 10 % of energy); (b) **WHO conditional** (< 5 %, "even greater health benefits"); (c) **AHA men** (≤ 36 g / 9 tsp / 150 kcal); (d) **AHA women & children ≥ 2 yo** (≤ 25 g / 6 tsp / 100 kcal). The tool returns grams, teaspoons (≈ sugar-cube equivalents), corresponding calories and the share of daily energy — directly comparable to the "Total sugars" line on a nutrition label per 100 g.
Enter a realistic daily energy intake (500–10 000 kcal).
Daily added-sugar ceiling
50.0 g
In teaspoons (sugar cubes)
11.9 tsp
Calories from added sugar
200 kcal
Share of daily energy
10.0%
References: WHO Sugars Guideline 2015 (ISBN 9789241549028); AHA Johnson et al. Circulation 2018. Conversion: 1 g = 4 kcal, 1 tsp ≈ 4.2 g. "Added sugars" exclude naturally-occurring sugars in fruit and dairy.
Formula
WHO percentage rule (share of total daily energy): grams = (kcal/day × percentage) / 4 kcal-per-gram e.g. 2000 kcal × 10 % / 4 = 50 g/day e.g. 2000 kcal × 5 % / 4 = 25 g/day AHA fixed caps (independent of total energy, by sex): AHA adult men = 36 g/day (= 9 tsp, 150 kcal) AHA adult women = 25 g/day (= 6 tsp, 100 kcal) Unit conversions: 1 g sugar = 4 kcal (USDA Food Composition) 1 tsp ≈ 4.2 g sugar (USDA, granulated) 1 sugar cube ≈ 4 g (typical retail brands)
- · **WHO 10 % vs 5 %**: the WHO 2015 *Sugars Guideline* issued two recommendations side-by-side. (1) **Strong**: adults and children should limit free-sugar intake to < 10 % of total energy (based on caries and body-weight evidence). (2) **Conditional**: further reduction to < 5 % brings additional benefit (based on the dental-caries dose-response). The < 5 % target is labelled "conditional" because the evidence is weaker but still suggestive. **In practice**: (a) a 2 000 kcal diet → 10 % = 50 g, 5 % = 25 g; (b) a single 330 mL can of Coke contains ~35 g sugar — already over the 5 % ceiling on its own; (c) a black coffee with two teaspoons (8.4 g) is fine; four teaspoons puts you near the 5 % cap.
- · **WHO vs AHA — the key difference**: WHO scales by *percentage of total energy*, which adapts linearly (athletes eating more can eat more sugar); AHA uses *fixed grams*, simpler but possibly too strict for ultra-endurance athletes (4 000 kcal/day) and too loose for sedentary adults (1 400 kcal/day). The **US Dietary Guidelines (DGA 2020–2025)** adopt "< 10 % of energy"; the **UK SACN 2015** uses 5 %; **Hong Kong's Centre for Health Protection** references the WHO standard. **What to pick**: (a) general use — WHO 10 %, easy to remember; (b) actively reducing sugar / prediabetes prevention — WHO 5 %; (c) want an absolute number, not a ratio — AHA.
- · **Added sugars ≠ total sugars**. Most nutrition labels (Hong Kong, Taiwan, pre-2020 US) only show *Total Sugars*, which lumps in the natural sugars of whole fruit; only the US FDA mandates a separate *Added Sugars* line as of 2020. **Quick rules**: (a) **whole fruit, plain milk, plain yoghurt** — high in sugar (an apple is ~10 g/100 g) but does *not* count as added sugar; (b) **fruit juice, dried fruit, fruit in syrup** — WHO 2015 explicitly counts these as free sugars; (c) **packaged foods** (soda, biscuits, bread, snacks) — if the ingredient list shows sucrose, syrup, honey, etc., treat the whole "sugars" line as added.
- · **Common hidden-sugar traps**: (a) **breakfast cereal & granola**: a 30 g serving can contain 8–15 g added sugar (30–60 % of the daily cap); (b) **flavoured yoghurt**: a 150 g strawberry-flavoured low-fat tub can hit 14–18 g; (c) **salad dressings**: a 30 g balsamic glaze or Thousand-Island serving hides 6–8 g; (d) **"healthy" smoothies**: a Starbucks grande can easily exceed 50 g; (e) **energy / protein bars**: 15–25 g of added sugar per bar is common. **Defence**: (1) learn to read the ingredient list (sugar by weight — if it's in the top 3 ingredients, that's a red flag); (2) check USDA FoodData Central (fdc.nal.usda.gov); (3) use Open Food Facts barcode scanning on the phone.
- · **Practical conversions**: (a) **330 mL can of Coke** ≈ 35 g (8.3 tsp) → 70 % of a 10 % daily cap; (b) **250 mL glass of orange juice** ≈ 22 g (5.2 tsp) → already 88 % of the AHA women's 25 g cap; (c) **50 g chocolate bar** ≈ 25 g sugar — a whole day's ceiling for women; (d) **HK-style lemon tea** ≈ 30 g (Hong Kong sweetness profiles run higher than Western equivalents); (e) **bubble milk tea, standard sweetness** ≈ 38–55 g depending on chain — one cup easily blows past the 5 % WHO target. **Reduction tactic**: order half-sugar / quarter-sugar / no-sugar variants; at HK cha-chaan-teng "少甜" ≈ 50 %, "走甜" = 0 %; at bubble-tea shops "半糖" ≈ 50 %, "微糖" ≈ 25 %, "無糖" = 0 %.
- · **References**: (1) **WHO** (2015), *Guideline: Sugars intake for adults and children*, ISBN 9789241549028 (strong < 10 %, conditional < 5 %); (2) **AHA**: Johnson R K et al. (2018), "Added Sugars and Cardiovascular Disease Risk in Children", *Circulation* 138:e160–e168; (3) **DGA 2020–2025** (USDA / HHS), *Dietary Guidelines for Americans*; (4) **SACN** (2015), *Carbohydrates and Health*, UK Public Health; (5) **USDA Food Composition Databases**, fdc.nal.usda.gov (calorie / gram conversions); (6) Te Morenga, L., Mallard, S., Mann, J. (2013), *BMJ* 346:e7492 — meta-analysis showing sugar reduction lowers body weight *independently* of overall calorie reduction.
Frequently asked
Does fruit count toward this daily limit?
**No — the natural sugars in *whole* fruit do not count as "added" sugars**. **WHO's "free sugars" definition** (2015) includes sucrose, glucose, fructose (as added ingredients), syrups (honey, maple, corn) and fruit juices / juice concentrates — but **not** the sugars naturally bound inside whole fruit, whole vegetables or milk lactose. **Why** — whole-fruit sugar comes packaged with fibre, water, vitamins and antioxidants; absorption is slower, the insulin spike is smaller, and observational studies consistently show whole-fruit intake is *inversely* associated with type-2 diabetes risk (apples, blueberries, grapes are the strongest signals; Muraki et al. 2013, *BMJ*). **Exceptions that *do* count**: (a) fruit juice (any form, including 100 % pure); (b) dried fruit (raisins, candied fruit) — sugar concentrates, fibre per gram drops; (c) canned fruit in syrup; (d) fruit purée used in processed foods; (e) coconut sugar (processed). **Practical guidance**: 2–4 whole-fruit servings per day (one serving ≈ a fist-sized piece) is recommended by both WHO and AHA and does *not* eat into your added-sugar budget.
Do non-nutritive sweeteners (aspartame, sucralose, stevia) count toward this limit?
**They do not count toward the added-sugar limit** — they contribute essentially zero calories and they are not sugars. **However**, in May 2023 the WHO issued a separate guideline (CG-NS) on *non-sugar sweeteners (NSS)* and **advised against** using them for weight control or NCD prevention. **Reasoning**: (a) observational evidence links NSS to *higher* long-run body weight, type-2 diabetes and CVD risk (causation not established but consistent); (b) impact on gut microbiota; (c) maintaining a high *taste-for-sweet* may sabotage overall sugar reduction. **WHO 2023 position**: an occasional diet Coke is not a problem, but *relying* on artificial sweeteners as a long-term sugar-reduction strategy is unwise; the goal should be re-training the palate to accept less sweetness overall. **Important exception**: diabetic patients on insulin — short-term NSS use is clinically reasonable (ADA 2023 still endorses), but the longer-term goal should still be reducing reliance on sweet flavours. **Practical advice for the general population**: (a) prefer unsweetened or lightly-sweetened whole foods; (b) using NSS during a transition period (the first months of sugar reduction) is acceptable; (c) long-term, your palate adapts and previously enjoyed foods will start to taste "too sweet".
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Daily Vitamin D Intake Target Calculator
Enter age, sex, life stage and your preferred unit (IU or mcg); the tool returns the daily vitamin D target from the NIH / IOM Dietary Reference Intakes — infants 400 IU AI, ages 1–70 600 IU and > 70 years 800 IU. It also shows the adult Tolerable Upper Intake Level (UL = 4 000 IU / day) and equivalent food servings (salmon, cod-liver oil, fortified milk, egg yolks, UV-exposed mushrooms).
Daily Potassium Intake Target Calculator
Enter age, sex and life stage; the tool returns the daily potassium mg target from the US NASEM 2019 DRI / NIH ODS Potassium Fact Sheet AI table (adult men 3 400 mg, women 2 600 mg, pregnancy 2 900 mg, lactation 2 800 mg) and converts it into common high-potassium food servings (banana, baked potato, avocado, spinach, white beans).
Daily Vitamin C Intake Target Calculator
Enter age, sex, life stage and smoking status; the tool returns the daily vitamin C mg target from the NIH / IOM Vitamin C Fact Sheet RDA (adult men 90 mg, women 75 mg, smokers +35 mg) and converts it into common food portions.
Daily Zinc Intake Target Calculator
Enter age, sex and life stage; the tool returns the daily zinc mg target from the NIH / IOM Zinc Fact Sheet RDA (adult men 11 mg, women 8 mg, pregnancy 11 mg, lactation 12 mg) — central to immunity, wound healing and the sense of taste / smell.
Daily Selenium Intake Target Calculator
Enter age, sex and life stage; the tool returns the daily selenium µg target from the NIH ODS Selenium Fact Sheet RDA (adults 55 µg, pregnancy 60 µg, lactation 70 µg, UL 400 µg) — a trace mineral essential to antioxidant defence, thyroid-hormone synthesis and immunity.
Daily Folate (Folic Acid) Intake Target Calculator
Enter age, sex and life stage; the tool returns the daily folate target in µg DFE from the NIH ODS Folate Fact Sheet RDA (adults 400, pregnancy 600, lactation 500, supplement UL 1000 µg / day) — the B-vitamin central to cell division, red-blood-cell formation and the prevention of fetal neural-tube defects.
Workout Rest Between Sets Calculator
Enter your training goal (maximal strength, hypertrophy, muscular endurance, power) and load intensity (% 1RM); the tool returns evidence-based rest-interval seconds between sets and the matching set / rep ranges, per NSCA Essentials of Strength Training (4th ed.) and ACSM guidelines.
Daily Vitamin B12 Intake Target Calculator
Look up your daily vitamin B12 RDA (μg/day) by age, sex and pregnancy / lactation status using NIH ODS values, with B12 amounts in common foods and supplementation notes for vegetarians and vegans.
Daily Iodine Intake Target Calculator
Look up your daily iodine RDA (μg/day) by age, sex and pregnancy / lactation status using NIH ODS values, with iodine content in iodised salt, seafood and common foods — guarding against deficiency (goitre) and excess (thyroid dysfunction).
Daily Vitamin A Intake Target Calculator
Look up your daily vitamin A RDA (μg RAE/day) and tolerable upper intake (UL) by age, sex and pregnancy / lactation status using NIH ODS values; converts retinol and β-carotene to RAE so you can avoid deficiency (night blindness) and retinol overdose.
HRV RMSSD Calculator (Heart Rate Variability)
Paste a list of RR intervals (in ms, comma- / space- / newline-separated); the tool returns RMSSD = √(mean((RR_{i+1} − RR_i)²)), SDNN, mean heart rate, and an interpretation following the 1996 Task Force HRV standards — handy for sanity-checking HRV figures from a Garmin, Apple Watch or Polar device.
Running Shoe Replacement Distance Calculator
Enter the shoe type (max-cushion, daily trainer, racing flat and more), runner weight tier and miles already logged; the tool uses the 300–500 mile sports-medicine wear-out range to return the miles remaining and a months-of-use estimate at your current cadence — handy for avoiding knee pain and plantar fasciitis from worn midsoles.
Caffeine Half-Life Decay Calculator
Caffeine's half-life averages about 5 hours — a 200 mg morning coffee still leaves ~100 mg in your blood at 5 pm and ~50 mg by 11 pm. Enter the dose and time taken to see exactly how much is still circulating when you try to sleep.
BMI Prime Calculator
BMI Prime = BMI ÷ 25 — expresses any BMI as a fraction of the normal-weight upper limit, so 1.00 means right at the cap and 1.20 means 20 % above it. Enter height and weight to read it instantly.
Spherical Equivalent (SE) Eye Prescription Calculator
Spherical equivalent SE = Sphere + (Cylinder ÷ 2) collapses a cylindrical (astigmatism) prescription into a single spherical power — routinely used for ordering contact lenses, refractive-surgery screening, and basic vision reports. Also returns the vertex-compensated corneal-plane power for high Rx.
Pregnancy Weight Gain Calculator (IOM Guidelines)
Enter pre-pregnancy height and weight (for BMI), gestational week and current weight; the tool returns the recommended total weight-gain range and weekly rate for singleton or twins based on the Institute of Medicine (IOM/NAM 2009) guidelines, comparing to actual gain.
Life Expectancy by Current Age Calculator
Enter current age and sex; using the WHO Global Health Observatory period life table, the tool estimates remaining life expectancy and projected age at death assuming present-day mortality.
Sunscreen Amount & SPF Protection Time Calculator
Using the dermatology 2 mg/cm² standard, work out how many grams of sunscreen (≈ the "shot-glass rule") you need for full body or each zone, then estimate reapplication interval from the classic "SPF × natural burn time" formula.
Hike Difficulty (Petzoldt Energy Miles) Calculator
Enter trail distance, elevation gain and walking pace; using outdoor educator Paul Petzoldt's "energy miles" rule (+2 miles per 1,000 ft gain), the tool returns effective distance, estimated time and a difficulty rating.
Marathon Fueling Gels Calculator
Enter race distance, projected finish time and carb intake target (g/h); based on the 30–90 g/h sports nutrition range, returns how many gels and at what spacing.
Cooper 12-Minute Run VO₂max Calculator
Enter your 12-minute run distance (m or mi), age and sex; the tool estimates VO₂max via Cooper's 1968 JAMA formula and maps it to a six-band age/sex fitness classification.
Max Heart Rate (HRmax) Formula Comparison Calculator
Enter age (and optional resting HR); compare HRmax estimates from Fox (220−age), Tanaka, Gellish and the Nes / HUNT3 formula side-by-side, plus Karvonen training-zone bpm ranges.
Bone Density T-Score / Z-Score Interpretation Calculator
Enter DEXA-scan T-score (and optional Z-score); classifies as normal / osteopenia / osteoporosis per WHO 1994 + ISCD 2019 criteria and shows relative fracture-risk multiplier.
Cycling FTP (Functional Threshold Power) Estimator + Training Zones
Enter your best 20-minute average power (watts) to get your FTP (= 20-min × 0.95) and the seven Coggan training zones (Z1 Recovery through Z7 Neuromuscular).
WHO Oral Rehydration Solution (ORS) Recipe Calculator
Enter the total water volume (ml) — get the grams of salt, glucose (or substitute sucrose) and optional potassium chloride needed for a WHO/UNICEF low-osmolarity ORS, the standard rehydration recipe for diarrhoea worldwide.
Reading Glasses (Near-Add) Diopter by Age Calculator
Enter your age and habitual reading distance — get a quick estimate of the near-add power (+0.50 to +3.00 D) for off-the-shelf reading glasses, based on the Hofstetter 1944 accommodation formula and standard optometric guidance.