Evidence-based nutrition writing, educational only, not medical adviceMedically reviewed by Dr. Shayaan Khan, MBBS
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Protein calculator
Nutrition and health, by the evidence

How much protein, fiber or sleep do you actually need?

Plain-language reviews of what published research and clinical guidelines say about protein, fiber, calories, sugar, sleep and water, with the number up front and the body that publishes it named. Every health page carries a named medical reviewer. Educational only, not medical advice.

A balanced meal of salmon, eggs, lentils, and leafy greens on a light table
Daily protein targetA quick estimate from your weight and activity, using commonly cited guideline ranges.
kg
Estimated daily target~84 g/dayA population guideline range, not a personal prescription.
See where these numbers come fromEducational estimate, not medical advice.

This is not medical advice. NourishMark publishes educational reviews of published research and clinical guidelines. It does not diagnose, treat, or replace your own clinician. Dr. Khan reviews NourishMark's health content for medical accuracy. He is not a registered dietitian, he does not hold a United States practising licence, and he is not your doctor. His review does not make anything here medical advice.How we research, write and review

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The questions readers open first

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Nutrition review

How Many Grams of Protein Do You Actually Need Per Day?

This evidence review covers how many grams of protein you need per day: the commonly cited baseline per kilogram, and why age, exercise, and goals shift it.

Read the review →Evidence review

How Many Calories Do You Actually Need Per Day? The Evidence

This evidence review explains what a daily calorie need is, how resting metabolism and activity combine into a total, and why every figure is individual.

Read the review →Evidence review

How Many Carbs Per Day? Daily Grams by Calorie Level

Daily carb intake in grams: roughly 225 to 325 g at 2,000 calories, or 45 to 65 percent of calories, with full tables by calorie level and by body weight.

Read the review →Evidence review

How Much Fiber Do You Need Per Day?

This evidence review lays out the commonly cited daily fiber guidance, near 25 grams for women and 38 for men, why most people fall short and how to close it.

Read the review →Evidence review

How Much Sugar Per Day? Grams, Limits, Daily Intake

Evidence review of the amount of sugar recommended per day: 25 g for women and 36 for men from the AHA, under 10 percent of calories, and who publishes each.

Read the review →Evidence review

How Many Hours of Sleep Do Adults Need? 8-Hour Rule Checked

How many hours of sleep do adults need? This evidence review traces the 7 to 9 hour range, how needs shift with age, and how weekend catch-up sleep repays.

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Evidence review70 reviewsFood reference9 reviewsNutrition review5 reviewsDigestive health2 reviewsReference2 reviews
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Quick reference

Commonly cited daily numbers

Guideline figures as published bodies state them, each linking to the full review and its sources. These are population guidelines, not personal targets, and not medical advice.

Carbs45 to 65%Of daily caloriesAdded sugar25 / 36 gUpper guide for women / menFiber25 / 38 gSuggested for women / menCaloriesIndividualSet by body size and activityProtein~0.8 g/kgBaseline per day, higher when activeSleep7 to 9 hrsFor most adultsWaterIt dependsNot simply eight glasses
Who writes this

Thorough, and evidence-based

Editorial process →

Two named people stand behind every review, and the limits of what they can tell you are stated as plainly as their credentials.

Hamza Hai, MBAEditor

Hamza Hai is the editor of NourishMark. She holds an MBA and reviews the site's articles against our editorial standards, checking that every figure is labelled for what it is, that nothing is presented as verified fact without a source the reader can check, and that the writing stays useful to a non-specialist.

Dr. Shayaan Khan, MBBSMedical reviewer

Dr. Shayaan Khan is the medical reviewer for NourishMark. He holds an MBBS from MGM Medical College, Navi Mumbai, and is the author of published research including a narrative review of postpartum anxiety and depression in Mental Health Science. He has taught physiology at university level. He reviews the site's health content for medical accuracy: that physiology and mechanisms are described correctly, that no claim is stated more strongly than the evidence behind it, and that anything specific to an individual reader is sent to that reader's own clinician.

And what his review does not mean. He is not a registered dietitian, he holds no United States practising licence, and he is not your doctor. The full scope of his review is set out in our editorial process.

How we researchEvery review explains what the published guidance says and attributes it to the body that publishes it, so you can check the current figure yourself. This is evidence-based general information, written to be educational, not medical advice, and never a substitute for your own clinician.
How we make moneyAt the time of writing this site carries no affiliate links and no advertising. No link earns a commission and no company pays for coverage. If that ever changes, the disclosure page will say so first and any paid link will be marked where it appears.
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