Skin and Ageing
The Collagen Best for Skin: Which Type, Form, and Dose Works
The collagen best for skin is a form, a type, and a dose, not a brand. Here is what the human trials actually used, and what collagen cannot do.
Read the guideYour body after 40, in numbers you can check.
Twenty-eight calculators, guides and meals for women in perimenopause and after. Every number carries its WHO, CDC or NIH source, and the ones you check stay on your own device.
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BMI Calculator
Check if your weight is in the healthy range for your height.
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Calorie Calculator
Find out how many calories you need per day to lose, maintain, or gain weight.
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Protein Intake Calculator
How much protein you need per day based on your weight and activity.
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High protein meals, weighed to your calories
See what your calorie and protein target looks like as food.
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Sleep Calculator
The best times to go to bed or wake up, based on 90 minute sleep cycles.
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Macro Calculator
Get your daily protein, carbs, and fat targets for your goal.
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Body Fat Calculator
Estimate your body fat percentage with the U.S. Navy method.
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Period Calculator
Predict your next periods and see your cycle at a glance.
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Intermittent Fasting Calculator
Get your fasting and eating window times for 16:8, 18:6, and more.
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Ideal Weight Calculator
See your ideal weight range based on four medical formulas.
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Waist to Hip Ratio Calculator
Check your waist to hip ratio and what it means for your health.
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Body Shape Calculator
Find your body type from your bust, waist, and hip measurements.
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BMR Calculator
Calculate your basal metabolic rate, the calories your body burns at rest.
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Water Intake Calculator
How much water you should drink per day, based on your body and lifestyle.
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Pregnancy Due Date Calculator
Estimate your due date from your last period, conception date, or IVF transfer.
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Ovulation Calculator
Find your fertile window and most likely ovulation days.
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Pregnancy Weight Gain Calculator
See the recommended weight gain for your stage of pregnancy.
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Heart Rate Zone Calculator
Find your target heart rate zones for fat burning and cardio training.
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Calories Burned Calculator
How many calories you burn walking, running, cycling, and more.
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Lean Body Mass Calculator
Estimate how much of your weight is muscle, bone, and organs.
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Creatine Calculator
Your creatine dose from body weight: a loading week or a steady dose, and how long each takes to work.
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Child Height Predictor
Estimate how tall your child will be as an adult, from parent heights.
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Steps to Calories Calculator
Turn your step count into calories burned and distance covered.
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Blood Pressure Checker
See which category your blood pressure reading falls into.
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Mean Arterial Pressure Calculator
Your mean arterial pressure from a blood pressure reading, and what the range means.
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Pain Scale
Rate pain from 0 to 10, see what the number means, and check the signs that need a doctor.
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Skin Type Quiz
Five questions to tell dry, normal, combination and oily skin apart, and whether it is sensitive.
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A1C Calculator
Convert between A1C and average blood sugar, both directions.
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Caffeine Calculator
Find your safe daily caffeine limit and what it equals in drinks.
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Guides this week
All guides
Fitness
Free Walking Programs for Weight Loss: What Works After 40
Walking helps you lose weight, but the real numbers and the honest limits after 40 are not what the thumbnails promise. Here is the research, plus a free eight-week plan.
Supplements
Hormone Balancing Supplements for Women: What the Evidence Shows
Most hormone balance pills promise more than they deliver. Here is which supplements for women over 40 have real evidence behind them, at what dose, and which ones are not worth the money.
Supplements
What Creatine Really Does for Women: The Effects the Evidence Supports
A numbers-first look at what creatine does for women, from bone and strength after menopause to mood, with the doses that work and the limits the trials admit.
High protein recipes, measured to the gram
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Listen to the guides
All recordings
The Collagen Best for Skin: Which Type, Form, and Dose Works
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Free Walking Programs for Weight Loss: What Works After 40
Listen to this article
Hormone Balancing Supplements for Women: What the Evidence Shows
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How this site works
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Sources first
Every number traces to the WHO, CDC, NIH, USDA or a peer-reviewed paper, listed at the bottom of the page. No source, no claim.
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Formulas shown
Every tool prints its formula and its floors: never below 1,200 kcal for women or 1,500 for men.
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Dated and corrected
Each page shows when it was last updated. Corrections are made in the text and noted at the bottom.
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Money, plainly
Ads come from Google and are kept out of our own text. The paid plan is the only thing we sell. We do not sell supplements.