The Power of Fiber: Why It's the Key to a Healthy Diet - Complete 2025 Guide

Dietary fiber is one of the most undervalued nutrients in modern nutrition, yet it's absolutely crucial for optimal health. Despite its importance, 95% of Americans don't consume enough fiber daily, missing out on its powerful benefits for weight management, heart health, and disease prevention. This comprehensive guide reveals why fiber deserves a starring role in your diet and how to harness its transformative power.

Understanding Dietary Fiber {#understanding-dietary-fiber}

What Is Dietary Fiber?

Scientific Definition:

Dietary fiber consists of indigestible plant compounds that pass through your digestive system relatively intact. Unlike other carbohydrates, fiber isn't broken down by human digestive enzymes, making it a unique nutrient with extraordinary health benefits.

Key Characteristics:

• Plant-based: Found exclusively in plant foods
• Indigestible: Passes through small intestine unabsorbed
• Fermentable: Beneficial bacteria in colon can break down some types
• Zero calories: Provides no energy but massive health benefits

Why Fiber Matters More Than Ever

Modern Diet Crisis:

• Average intake: 15g daily (half the recommended amount)
• Processed food dominance: 60% of calories from ultra-processed foods
• Fiber removal: Food processing strips away natural fiber
• Health consequences: Rising rates of obesity, diabetes, heart disease

Historical Context:

• Paleolithic diet: 100-150g fiber daily
• Early 1900s: 40-50g daily average
• Current intake: 15g daily average
• Recommended: 25-35g daily minimum

Types of Fiber Explained {#types-of-fiber-explained}

Soluble Fiber

Characteristics:

• Dissolves in water: Forms gel-like substance
• Fermentable: Feeds beneficial gut bacteria
• Cholesterol-lowering: Binds bile acids
• Blood sugar control: Slows glucose absorption

Top Soluble Fiber Sources:

Health Benefits:

• Lowers LDL cholesterol by 5-10%
• Reduces blood sugar spikes by 20-30%
• Feeds beneficial bacteria (prebiotics)
• Increases satiety and fullness

Insoluble Fiber

Characteristics:

• Doesn't dissolve: Remains intact through digestion
• Adds bulk: Increases stool volume
• Speeds transit: Promotes regular bowel movements
• Mechanical action: Scrubs intestinal walls clean

Top Insoluble Fiber Sources:

Health Benefits:

• Prevents constipation
• Reduces hemorrhoid risk
• Supports healthy gut transit time
• May reduce colon cancer risk

Functional Fibers

Added Fibers:

• Inulin: Chicory root extract, prebiotic
• Psyllium: Plantago seed husks, cholesterol-lowering
• Methylcellulose: Synthetic fiber, bulking agent
• Resistant starch: Modified starches, blood sugar control

Effectiveness:

• Natural vs added: Whole foods provide superior benefits
• Synergistic effects: Natural fibers work with other nutrients
• Processing matters: Isolated fibers less effective than whole foods

Health Benefits of Fiber {#health-benefits-of-fiber}

Digestive Health

Constipation Prevention:

• Mechanism: Adds bulk and softens stool
• Effectiveness: 77% improvement in bowel regularity
• Optimal intake: 25-35g daily with adequate water
• Timeline: Benefits seen within 1-3 days

Gut Microbiome Support:

• Prebiotic effect: Feeds beneficial bacteria
• Diversity increase: Higher fiber = more bacterial species
• Short-chain fatty acids: Bacterial fermentation produces beneficial compounds
• Immune function: 70% of immune system located in gut

Weight Management

Satiety Enhancement:

• Mechanism: Slows eating, increases fullness signals
• Calorie reduction: 14% fewer calories consumed naturally
• Weight loss: Additional 10g fiber = 4.2 lbs lost over 4 months
• Long-term success: High-fiber diets show better maintenance

Metabolic Benefits:

• Thermic effect: 10% more calories burned digesting high-fiber meals
• Fat absorption: Reduces dietary fat absorption by 3-4%
• Insulin sensitivity: Improves glucose metabolism
• Appetite hormones: Increases GLP-1, reduces ghrelin

Cardiovascular Health

Cholesterol Reduction:

• LDL cholesterol: 5-10% reduction with 10g soluble fiber daily
• Mechanism: Binds bile acids, forces cholesterol use
• Timeline: Benefits seen within 4-6 weeks
• Synergy: Works best with low saturated fat diet

Blood Pressure Benefits:

• Systolic reduction: 2-3 mmHg average decrease
• Diastolic reduction: 1-2 mmHg average decrease
• Mechanism: Improved arterial flexibility
• Population impact: Could prevent 15,000 heart attacks annually

Disease Prevention

Type 2 Diabetes:

• Risk reduction: 20-30% lower risk with high fiber intake
• Blood sugar control: 15-25% improvement in glucose levels
• Insulin sensitivity: 25% improvement in insulin function
• Mechanism: Slows glucose absorption, improves gut hormones

Cancer Prevention:

• Colorectal cancer: 10% risk reduction per 10g fiber daily
• Breast cancer: 5% risk reduction with high fiber intake
• Mechanism: Dilutes carcinogens, speeds elimination
• Protective compounds: Antioxidants and phytochemicals in fiber-rich foods

Daily Fiber Requirements {#daily-fiber-requirements}

Age and Gender Guidelines

Adult Recommendations:

Children's Needs:

• Ages 1-3: 19g daily
• Ages 4-8: 25g daily
• Ages 9-13: Boys 31g, Girls 26g daily
• Ages 14-18: Boys 38g, Girls 26g daily

Current Intake vs Recommendations

Fiber Gap Analysis:

• Average American intake: 15g daily
• Recommended minimum: 25-35g daily
• Optimal intake: 35-50g daily
• Shortfall: 10-20g daily for most people

Global Comparisons:

• Rural Africa: 60-120g daily (traditional diets)
• Mediterranean regions: 30-40g daily
• Asian countries: 25-35g daily
• Western countries: 12-18g daily

Gradual Increase Strategy

Week-by-Week Plan:

• Week 1: Add 5g daily (current + 5g)
• Week 2: Add another 5g daily (current + 10g)
• Week 3: Add another 5g daily (current + 15g)
• Week 4: Reach target intake (25-35g daily)

Why Gradual Matters:

• Prevents digestive upset: Bloating, gas, cramping
• Allows adaptation: Gut bacteria adjust to increased fiber
• Improves compliance: Easier to maintain long-term
• Water intake: Increase fluids as fiber increases

Best High-Fiber Foods {#best-high-fiber-foods}

Fruits (High-Fiber Champions)

Top Fiber Fruits:

Preparation Tips:

• Keep skins on: Apple and pear skins contain most fiber
• Choose whole fruits: Juice removes fiber content
• Frozen options: Retain fiber content when fresh unavailable
• Dried fruits: Higher fiber concentration but watch portions

Vegetables (Fiber Powerhouses)

Highest Fiber Vegetables:

Preparation Strategies:

• Minimal processing: Light cooking preserves fiber structure
• Include stems: Broccoli stems contain significant fiber
• Variety matters: Different vegetables provide different fiber types
• Raw vs cooked: Both provide benefits, vary preparation

Legumes (Fiber Superstars)

Legume Fiber Champions:

Preparation Methods:

• Soaking: Reduces cooking time, improves digestibility
• Gradual introduction: Start with 1/4 cup servings
• Spice additions: Cumin, ginger aid digestion
• Canned options: Rinse to reduce sodium, retain fiber

Whole Grains (Sustained Energy)

Whole Grain Fiber Content:

Selection Tips:

• Read labels: "Whole grain" should be first ingredient
• Avoid refined: White rice, white bread have minimal fiber
• Ancient grains: Farro, spelt, amaranth offer variety
• Breakfast choices: Steel-cut oats superior to instant

Nuts and Seeds (Concentrated Nutrition)

High-Fiber Nuts and Seeds:

Usage Strategies:

• Ground flax/chia: Better absorption than whole seeds
• Portion control: High calorie density, stick to 1 oz servings
• Variety rotation: Different nuts provide different nutrients
• Soaking: Improves digestibility for some people

Fiber and Weight Management {#fiber-and-weight-management}

Satiety Mechanisms

How Fiber Promotes Fullness:

• Mechanical fullness: Adds volume without calories
• Slower eating: Requires more chewing, extends meal time
• Hormone regulation: Increases GLP-1, CCK (fullness hormones)
• Gastric emptying: Slows stomach emptying, prolongs satiety

Research Findings:

• Calorie reduction: 14% fewer calories consumed with high-fiber meals
• Appetite duration: Fullness lasts 2-3 hours longer
• Snacking reduction: 25% less between-meal eating
• Portion control: Natural reduction in serving sizes

Weight Loss Studies

Clinical Evidence:

• 12-month study: High-fiber group lost 5.1 lbs vs 1.9 lbs control
• Meta-analysis: Each 14g fiber increase = 10% calorie reduction
• Long-term success: High-fiber dieters maintain weight loss better
• Visceral fat: Soluble fiber specifically reduces belly fat

Optimal Fiber for Weight Loss:

• Target intake: 35-40g daily for weight loss
• Timing: Distribute throughout day, not single large dose
• Food sources: Whole foods superior to supplements
• Water intake: 8-10 glasses daily to support fiber function

Practical Weight Management Tips

High-Fiber Meal Strategies:

• Start meals with salad: 2-3g fiber, reduces main course intake
• Choose whole grains: Brown rice vs white rice saves 100 calories
• Bean additions: Add 1/2 cup beans to meals for 6-8g fiber
• Fruit desserts: Replace processed sweets with high-fiber fruits

Snack Swaps:

• Instead of chips: Air-popped popcorn (3g fiber per cup)
• Instead of cookies: Apple with almond butter (5g fiber)
• Instead of candy: Berries with Greek yogurt (6g fiber)
• Instead of crackers: Vegetables with hummus (4g fiber)

Fiber for Heart Health {#fiber-for-heart-health}

Cholesterol Management

Soluble Fiber Mechanism:

• Bile acid binding: Forces body to use cholesterol for bile production
• Cholesterol synthesis: Reduces liver cholesterol production
• LDL reduction: 5-10% decrease with 10g soluble fiber daily
• HDL protection: Maintains beneficial cholesterol levels

Clinical Studies:

• Oat study: 3g beta-glucan daily reduced LDL by 7%
• Bean research: 1/2 cup daily lowered cholesterol 8%
• Psyllium trials: 10g daily reduced LDL by 13%
• Combined approach: Diet + fiber more effective than either alone

Blood Pressure Benefits

Cardiovascular Mechanisms:

• Arterial flexibility: Fiber improves endothelial function
• Sodium balance: Potassium-rich fiber foods counter sodium
• Weight management: Fiber-induced weight loss lowers BP
• Inflammation reduction: Anti-inflammatory compounds in fiber foods

Population Studies:

• DASH diet: High-fiber approach reduces BP by 11/6 mmHg
• Mediterranean diet: Fiber-rich pattern lowers heart disease 30%
• Nurses' Health Study: High fiber intake = 40% lower heart attack risk
• Meta-analysis: 10g fiber daily = 14% lower heart disease risk

Heart-Healthy Fiber Plan

Daily Fiber Distribution:

• Breakfast: 8-10g (oatmeal with berries)
• Lunch: 10-12g (salad with beans and vegetables)
• Dinner: 8-10g (quinoa with roasted vegetables)
• Snacks: 4-6g (apple with nuts, vegetables with hummus)
• Total: 30-38g daily

Weekly Heart-Healthy Menu:

• Monday: Oat bran cereal, lentil soup, salmon with quinoa
• Tuesday: Smoothie with flax, bean salad, brown rice stir-fry
• Wednesday: Whole grain toast, chickpea curry, barley pilaf
• Thursday: Chia pudding, vegetable soup, whole wheat pasta
• Friday: Quinoa bowl, black bean tacos, roasted vegetables
• Saturday: Oatmeal pancakes, split pea soup, wild rice
• Sunday: Fruit salad, three-bean chili, sweet potato

Gut Health and Microbiome {#gut-health-and-microbiome}

Prebiotic Power

Fiber as Prebiotic:

• Definition: Food for beneficial gut bacteria
• Fermentation: Bacteria break down fiber into beneficial compounds
• Short-chain fatty acids: Butyrate, acetate, propionate production
• Immune support: 70% of immune system in gut

Best Prebiotic Fibers:

• Inulin: Jerusalem artichokes, garlic, onions
• Fructooligosaccharides: Bananas, asparagus, leeks
• Beta-glucan: Oats, barley, mushrooms
• Resistant starch: Cooled potatoes, green bananas
• Pectin: Apples, citrus fruits, carrots

Microbiome Diversity

Fiber and Bacterial Diversity:

• Species richness: High fiber = more bacterial species
• Beneficial bacteria: Bifidobacterium, Lactobacillus increase
• Harmful bacteria: Pathogenic species decrease
• Stability: Diverse microbiome more resilient to disruption

Research Findings:

• Rural populations: 50+ bacterial species vs 15-20 in Western diets
• Fiber intervention: 25% increase in beneficial bacteria within 2 weeks
• Antibiotic recovery: High-fiber diet speeds microbiome restoration
• Generational effects: Low-fiber diets reduce diversity across generations

Digestive Health Benefits

Gut Function Improvements:

• Transit time: Optimal 12-24 hours for complete digestion
• Stool consistency: Bristol scale 3-4 (ideal formation)
• Regularity: Daily bowel movements without straining
• Gut barrier: Stronger intestinal wall prevents leaky gut

Condition Management:

• IBS symptoms: Soluble fiber reduces symptoms 50%
• Diverticulosis: High fiber prevents complications
• Inflammatory bowel: Certain fibers reduce inflammation
• Constipation: 77% improvement with adequate fiber

How to Increase Fiber Intake {#how-to-increase-fiber-intake}

Gradual Introduction Strategy

4-Week Fiber Increase Plan:

Daily Implementation:

• Morning: Add berries to cereal (+3g)
• Lunch: Choose whole grain bread (+3g)
• Afternoon: Apple with skin snack (+4g)
• Dinner: Include 1/2 cup beans (+6g)
• Evening: Small handful nuts (+3g)
• Total: +19g daily

Meal-by-Meal Strategies

Breakfast Fiber Boosters:

• Oatmeal base: Steel-cut oats (4g) + berries (4g) + ground flax (4g) = 12g
• Smoothie power: Spinach (2g) + banana (3g) + chia seeds (5g) = 10g
• Whole grain toast: 2 slices (6g) + avocado (5g) = 11g
• Yogurt parfait: Greek yogurt + granola (3g) + berries (4g) = 7g

Lunch Fiber Additions:

• Salad foundation: Mixed greens (2g) + chickpeas (6g) + vegetables (3g) = 11g
• Soup upgrade: Lentil soup (8g) + whole grain roll (3g) = 11g
• Sandwich improvement: Whole grain bread (6g) + vegetables (2g) = 8g
• Grain bowl: Quinoa (5g) + black beans (7g) + vegetables (4g) = 16g

Dinner Fiber Focus:

• Vegetable emphasis: 2 cups mixed vegetables (8g)
• Whole grain sides: Brown rice (4g) or quinoa (5g)
• Legume additions: Add beans to any dish (+6-8g)
• Salad starter: Begin meal with fiber-rich salad

Smart Substitutions

Easy Fiber Swaps:

Cooking Modifications:

• Add vegetables: Include in sauces, soups, casseroles
• Bean additions: Mix into rice, pasta, salads
• Skin retention: Keep peels on potatoes, apples, pears
• Whole grain flours: Replace 25-50% of white flour in recipes

Common Fiber Mistakes {#common-fiber-mistakes}

Mistake #1: Too Much Too Fast

The Problem:

• Digestive distress: Bloating, gas, cramping, diarrhea
• Bacterial overwhelm: Gut microbes can't adapt quickly
• Compliance failure: Discomfort leads to abandoning high-fiber diet
• Water imbalance: Insufficient fluid intake with increased fiber

The Solution:

• Gradual increase: Add 5g weekly until reaching target
• Monitor symptoms: Reduce if experiencing significant discomfort
• Patience required: Full adaptation takes 2-4 weeks
• Individual variation: Some people need slower progression

Mistake #2: Insufficient Water Intake

The Problem:

• Constipation paradox: More fiber without water worsens constipation
• Fiber binding: Absorbs water, can create hard stools
• Digestive blockage: Risk of impaction with severe dehydration
• Reduced benefits: Fiber needs water to function properly

The Solution:

• Water formula: 8 oz water per 5g fiber consumed
• Gradual increase: Add water as fiber increases
• Timing matters: Drink water with fiber-rich meals
• Monitor urine: Pale yellow indicates adequate hydration

Mistake #3: Relying Only on Supplements

The Problem:

• Isolated nutrients: Missing synergistic compounds in whole foods
• Limited variety: Single fiber type vs multiple types in foods
• Reduced satiety: Supplements don't provide fullness like whole foods
• Cost inefficiency: More expensive than food sources

The Solution:

• Food first: Prioritize whole food sources
• Supplement support: Use only to fill specific gaps
• Variety emphasis: Include multiple fiber types daily
• Whole food benefits: Vitamins, minerals, antioxidants included

Mistake #4: Ignoring Fiber Types

The Problem:

• Imbalanced intake: Too much of one type, not enough of another
• Missing benefits: Different fibers provide different health benefits
• Digestive issues: Some people sensitive to certain fiber types
• Suboptimal results: Not maximizing fiber's potential

The Solution:

• Soluble sources: Oats, beans, apples, barley
• Insoluble sources: Whole grains, vegetables, nuts
• Variety rotation: Different foods throughout week
• Individual tolerance: Identify which fibers work best for you

Mistake #5: Processed "High-Fiber" Foods

The Problem:

• Added fibers: Isolated fibers added to processed foods
• Marketing deception: "High fiber" doesn't mean healthy
• Missing nutrients: Lack vitamins, minerals of whole foods
• Higher cost: Pay premium for inferior nutrition

The Solution:

• Whole food focus: Choose naturally fiber-rich foods
• Read ingredients: Avoid long lists of additives
• Natural sources: Fruits, vegetables, legumes, whole grains
• Cost savings: Whole foods often less expensive

7-Day High-Fiber Meal Plan {#7-day-high-fiber-meal-plan}

Day 1: Foundation Building (28g fiber)

Breakfast (8g fiber):

• Steel-cut oatmeal (1 cup): 4g
• Mixed berries (1/2 cup): 4g
• Coffee or tea

Lunch (10g fiber):

• Large salad with mixed greens (2 cups): 4g
• Chickpeas (1/2 cup): 6g
• Olive oil vinaigrette

Dinner (8g fiber):

• Grilled chicken breast
• Quinoa (1 cup cooked): 5g
• Steamed broccoli (1 cup): 3g

Snack (2g fiber):

• Apple slices (1 medium): 2g

Day 2: Legume Power (32g fiber)

Breakfast (6g fiber):

• Whole grain toast (2 slices): 6g
• Avocado (1/2 medium): 5g
• Sliced tomato

Lunch (12g fiber):

• Lentil soup (1.5 cups): 12g
• Side salad with vegetables: 3g

Dinner (10g fiber):

• Black bean and vegetable stir-fry: 8g
• Brown rice (1 cup): 4g

Snack (4g fiber):

• Pear with skin (1 medium): 4g

Day 3: Vegetable Focus (30g fiber)

Breakfast (7g fiber):

• Smoothie with spinach (1 cup): 2g
• Banana (1 medium): 3g
• Ground flaxseed (1 tbsp): 2g

Lunch (11g fiber):

• Three-bean salad (1 cup): 9g
• Whole grain crackers (6): 2g

Dinner (9g fiber):

• Baked sweet potato with skin: 4g
• Green beans (1 cup): 4g
• Lean protein

Snack (3g fiber):

• Almonds (1 oz): 3g

Day 4: Whole Grain Day (35g fiber)

Breakfast (10g fiber):

• Bran cereal (1 cup): 10g
• Sliced banana: 3g
• Low-fat milk

Lunch (12g fiber):

• Whole wheat pasta salad (1.5 cups): 9g
• Mixed vegetables: 3g

Dinner (10g fiber):

• Barley pilaf (1 cup): 6g
• Roasted Brussels sprouts (1 cup): 4g

Snack (3g fiber):

• Popcorn (3 cups air-popped): 3g

Day 5: Bean Bonanza (38g fiber)

Breakfast (8g fiber):

• Overnight oats with chia seeds: 8g
• Fresh berries: 4g

Lunch (15g fiber):

• Navy bean soup (2 cups): 15g
• Whole grain roll: 3g

Dinner (12g fiber):

• Kidney bean chili (1.5 cups): 12g
• Side of steamed vegetables: 4g

Snack (3g fiber):

• Orange (1 medium): 3g

Day 6: Fruit and Vegetable Variety (33g fiber)

Breakfast (9g fiber):

• Greek yogurt parfait with granola: 4g
• Mixed berries (1 cup): 8g

Lunch (12g fiber):

• Large vegetable and hummus wrap: 8g
• Side of raw vegetables: 4g

Dinner (9g fiber):

• Stuffed bell peppers with quinoa: 9g
• Side salad: 3g

Snack (3g fiber):

• Apple with almond butter: 4g

Day 7: Balanced Approach (36g fiber)

Breakfast (11g fiber):

• Whole grain pancakes (2): 6g
• Raspberry topping (1/2 cup): 4g
• Ground flaxseed (1 tbsp): 2g

Lunch (13g fiber):

• Split pea soup (2 cups): 13g
• Whole grain bread (1 slice): 3g

Dinner (9g fiber):

• Wild rice blend (1 cup): 5g
• Artichoke (1 medium): 10g
• Lean protein

Snack (3g fiber):

• Trail mix with dried fruit and nuts: 3g

Weekly Meal Prep Tips

Batch Cooking:

• Sunday prep: Cook large batches of beans, quinoa, brown rice
• Vegetable prep: Wash, chop vegetables for easy weekday use
• Soup preparation: Make large pots of high-fiber soups
• Overnight oats: Prepare 3-4 servings at once

Storage Solutions:

• Bean portions: Freeze in 1-cup portions for easy use
• Grain storage: Refrigerate cooked grains up to 5 days
• Vegetable prep: Store cut vegetables in airtight containers
• Smoothie packs: Pre-portion frozen smoothie ingredients

FAQs {#faqs}

How quickly will I see benefits from increasing fiber?

Most people notice improved digestion within 1-3 days of increasing fiber intake. Cholesterol-lowering effects typically appear within 4-6 weeks, while weight management benefits may take 2-3 months to fully manifest. The key is consistent, gradual increase with adequate water intake.

Can I get too much fiber?

Yes, excessive fiber intake (over 50-60g daily) can cause digestive distress, nutrient malabsorption, and intestinal blockage. Most people do well with 25-35g daily. If you experience persistent bloating, gas, or changes in bowel habits, reduce intake and consult a healthcare provider.

Should I take fiber supplements?

Whole food sources are superior to supplements because they provide additional nutrients and various fiber types. However, supplements can help fill gaps when whole food intake is insufficient. Choose supplements with multiple fiber types and always increase water intake accordingly.

Why do I get gas when I increase fiber?

Gas production is normal when increasing fiber because gut bacteria ferment the fiber, producing gas as a byproduct. This typically decreases as your microbiome adapts (2-4 weeks). Gradual increase, adequate water, and digestive enzymes can help minimize discomfort.

Is fiber safe for people with digestive conditions?

People with IBS, Crohn's disease, or other digestive conditions should work with healthcare providers to determine appropriate fiber intake. Soluble fiber is often better tolerated than insoluble fiber in these conditions. Start with small amounts and monitor symptoms carefully.

Can children eat high-fiber diets safely?

Yes, children benefit from age-appropriate fiber intake. The formula is age + 5 grams daily (e.g., 10-year-old needs 15g daily). Focus on naturally fiber-rich foods rather than supplements, and ensure adequate fluid intake to prevent constipation.

Does cooking destroy fiber?

Cooking doesn't destroy fiber, but it can change its structure and effectiveness. Light cooking (steaming, sautéing) preserves most benefits, while overcooking may reduce some fiber's effectiveness. Both raw and cooked high-fiber foods provide benefits.

How does fiber help with weight loss?

Fiber promotes weight loss through multiple mechanisms: increased satiety, reduced calorie absorption, slower eating pace, improved blood sugar control, and beneficial changes in gut hormones. The combination of these effects naturally reduces calorie intake without conscious restriction.

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Ready to harness fiber's transformative power? Start with our gradual 4-week increase plan, focusing on whole food sources and adequate hydration. Track your daily intake and notice improvements in energy, digestion, and overall health.

Next Steps:

• Calculate your current fiber intake using a food diary
• Choose 3 new high-fiber foods to try this week
• Increase water intake by 2-3 glasses daily
• Join our community for ongoing support and fiber-rich recipe ideas

Disclaimer: This information is for educational purposes only and not intended as medical advice. Consult with a healthcare provider before making significant dietary changes, especially if you have digestive conditions or take medications.