Fit Nutrition library

Nutrition Guides

Clear, practical nutrition guides that turn everyday food questions into simple decisions — how much protein you actually need, what to eat before a workout, how to read a label, and which choices are worth your attention. Every guide is written in plain language and backed by trusted sources, so you can act on it the same day.

143 guides

All guides

Alcohol and Athletic Performance: Hydration, Recovery, and Body Composition ImpactMuscle & Performance

Alcohol and Athletic Performance: Hydration, Recovery, and Body Composition Impact

Alcohol athletic performance affects hydration, muscle recovery, and body composition. Learn how timing and amount impact your fitness goals.

6 min read
The Gut and Athletic Performance: Why Hard Training Upsets Your StomachMuscle & Performance

The Gut and Athletic Performance: Why Hard Training Upsets Your Stomach

Why endurance exercise causes stomach trouble: splanchnic blood flow, the 60 and 90 g/h carbohydrate limits, the 2% dehydration threshold, and what probiotic studies really found.

8 min read
Budget-Friendly Nutrition for Fitness: Building Muscle and Losing Fat Without Expensive FoodsNutrition Basics

Budget-Friendly Nutrition for Fitness: Building Muscle and Losing Fat Without Expensive Foods

Learn how to fuel muscle building and fat loss with cheap protein sources, budget meal prep, and practical whole foods instead of expensive supplements.

6 min read
Seasonal Eating: What Actually ChangesFoods & Nutrients

Seasonal Eating: What Actually Changes

Is seasonal produce more nutritious? No agency says so. What storage really does to vitamins, how frozen compares with fresh, and what "local" legally means.

8 min read
Vitamin D Rich Foods: The Short, Real ListVitamins & Supplements

Vitamin D Rich Foods: The Short, Real List

The list of foods with meaningful vitamin D is short. What they are, how much you need, and when sun and supplements come into it.

5 min read
How Nutrition Affects Performance: The Numbers That MatterMuscle & Performance

How Nutrition Affects Performance: The Numbers That Matter

Macronutrients—carbohydrates, proteins, and fats—are the cornerstone of any athlete's diet, playing a pivotal role in fueling physical..

6 min read
How to Read Nutrition Labels: The 30-Second FDA MethodNutrition Basics

How to Read Nutrition Labels: The 30-Second FDA Method

Learn how to read nutrition labels using the FDA's own 5/20 rule. See which four lines matter, what %DV means, and how to spot added sugars fast.

8 min read
Protein Quality: How Food Is Actually ScoredProtein

Protein Quality: How Food Is Actually Scored

How protein quality is scored: PDCAAS on US labels and why it is capped, DIAAS values for whey, beef, soy, wheat and rice, and whether proteins must be combined at a meal.

9 min read
How to Start Eating Healthy: Seven Changes, One at a TimeNutrition Basics

How to Start Eating Healthy: Seven Changes, One at a Time

A sequenced beginner guide built on NIDDK habit-change guidance and the 2026 Dietary Guidelines — plus five pieces of starter advice you can safely ignore.

9 min read
Does Food Affect Mood? What the Evidence ShowsWeight Loss

Does Food Affect Mood? What the Evidence Shows

Diet and mood are linked, but most of the popular claims are not supported. What the evidence shows about food, supplements, anxiety and well-being.

5 min read
Complete Guide to Food TrackingMindful Eating

Complete Guide to Food Tracking

How to start food logging, the tools worth using, the mistakes that make tracking inaccurate, and how to stay consistent past the first fortnight.

10 min read
Sodium Intake Guidelines and Low-Sodium Meal IdeasFoods & Nutrients

Sodium Intake Guidelines and Low-Sodium Meal Ideas

The recommended daily sodium limits, how to read sodium on a label, planning low-sodium meals that still taste good, and the usual pitfalls.

10 min read
Fiber Benefits: What Federal Sources Actually SupportFoods & Nutrients

Fiber Benefits: What Federal Sources Actually Support

Fiber intake benefits your digestive health, weight management, and disease prevention. Learn daily recommendations, soluble vs. insoluble fiber, and top food sources.

7 min read
Understanding Hunger Hormones: Why You’re Hungry and How to Control Appetite NaturallyMindful Eating

Understanding Hunger Hormones: Why You’re Hungry and How to Control Appetite Naturally

Hunger hormones control your appetite through ghrelin and leptin. Learn why you're hungry and proven ways to balance them naturally. Discover how.

7 min read
Dietary Supplements: What FDA Does and Does Not CheckVitamins & Supplements

Dietary Supplements: What FDA Does and Does Not Check

Dietary supplements and vitamins play a significant role in modern nutrition, serving as a means to enhance overall health and well-being. These..

7 min read
Mindful Exercise: A Complete Guide to Combining Mindfulness and MovementPhysical Activity

Mindful Exercise: A Complete Guide to Combining Mindfulness and Movement

Mindful exercise guide teaches breath techniques for stress reduction workouts. Learn mindfulness during cardio and yoga breathing tips. Find out why.

4 min read
Is Quinoa Healthy? The Benefits That Hold UpSuperfoods

Is Quinoa Healthy? The Benefits That Hold Up

Quinoa is a complete protein and a decent fibre source. Which health claims survive scrutiny, which come with an asterisk, and how it compares on the numbers.

4 min read
Homemade Electrolyte Drink: Recipe and When You Need OneHealthy Recipes

Homemade Electrolyte Drink: Recipe and When You Need One

A homemade electrolyte drink is water, 1/4 tsp salt and juice. Here is the recipe, what it delivers in sodium and potassium, and when water is enough.

7 min read