Intermittent Fasting: What You Need to Know Before You Start

Intermittent fasting has become one of the most popular approaches to managing eating patterns, weight and metabolic health. Unlike traditional diets that focus primarily on what you eat, intermittent fasting focuses on when you eat.

From the popular 16:8 method to occasional longer fasting periods, there are several ways to incorporate intermittent fasting into everyday life. But fasting isn't suitable for everyone, and simply skipping meals doesn't automatically create a healthy lifestyle.

Before you start, it's important to understand how intermittent fasting works, what you can eat and drink while fasting, how to maintain good nutrition, and how supplements may fit into your routine.

What Is Intermittent Fasting?

Intermittent fasting (IF) is an eating pattern that alternates between periods of eating and fasting.

Rather than prescribing specific foods, it establishes periods during which you eat and periods during which you consume little or no energy.

Quick Answer: How Does Intermittent Fasting Work?

Intermittent fasting works by extending the period between meals. During the fasting period, calorie-containing foods and drinks are avoided. During the eating window, the focus should remain on a balanced, nutrient-rich diet that provides sufficient energy, protein, vitamins, minerals and other essential nutrients.

What Are the Most Popular Types of Intermittent Fasting?

There is no single way to practise intermittent fasting. Some approaches are considerably easier to incorporate into everyday life than others.

16:8 Intermittent Fasting

The 16:8 method involves fasting for 16 hours and eating within an eight-hour window.

For example, someone might finish dinner at 8:00 pm and have their first meal the following day at 12:00 pm.

This is one of the most popular approaches because much of the fasting period occurs while sleeping.

14:10 Intermittent Fasting

The 14:10 method provides a 10-hour eating window followed by a 14-hour fast.

For beginners, this can be a more manageable introduction to time-restricted eating.

5:2 Diet

With the 5:2 approach, people generally eat normally on five days of the week and substantially restrict calorie intake on two non-consecutive days.

This differs from daily time-restricted eating because the focus is on particular days rather than a daily fasting window.

Alternate-Day Fasting

Alternate-day fasting involves alternating between regular eating days and days of fasting or significant calorie restriction.

This is a more demanding approach and may be difficult to sustain for some people.

What Happens to Your Body During Intermittent Fasting?

After eating, your body digests and absorbs nutrients from your meal and uses or stores the available energy.

As the period without food becomes longer, insulin levels generally decline and the body increasingly draws upon stored energy.

Researchers continue to investigate how different fasting patterns may affect metabolic health, body weight, blood glucose regulation and other health markers.

However, intermittent fasting should not be viewed as a shortcut to optimal health. The nutritional quality and total amount of food you consume still matter.

What Are the Potential Benefits of Intermittent Fasting?

Research into intermittent fasting and time-restricted eating has identified several potential benefits, although results vary depending on the individual and the fasting method used.

Potential benefits may include:

• Supporting weight management by helping some people reduce overall calorie intake
• Improvements in certain markers of metabolic health
• Better blood glucose control in some populations
• A simpler eating routine for people who prefer fewer meals
• Reduced late-night eating and snacking

Importantly, intermittent fasting isn't necessarily superior to other healthy approaches to calorie control. For many people, its biggest advantage may simply be that a defined eating window makes their diet easier to manage consistently.

Is Intermittent Fasting Good for Weight Loss?

Intermittent fasting can help with weight loss, but fasting itself doesn't override energy balance.

If a shorter eating window causes you to consume fewer calories over time, body weight may decrease. However, consuming excessive calories during your eating window can reduce or eliminate this effect.

The quality of your diet also remains important.

A successful approach should prioritise:

• Adequate protein
• Vegetables and fruit
• Whole grains and fibre-rich carbohydrates
• Healthy fats
• Sufficient vitamins and minerals
• Appropriate hydration

Think of intermittent fasting as an eating schedule rather than a licence to ignore nutrition.

What Can You Drink During Intermittent Fasting?

During a strict fast, the simplest choice is water.

People practising intermittent fasting also commonly consume calorie-free beverages such as unsweetened tea or black coffee.

Avoid adding sugar, milk, cream or other calorie-containing ingredients if your objective is to maintain a calorie-free fasting period.

Staying adequately hydrated is particularly important when you aren't obtaining water from foods and meals throughout the fasting period.

Do Vitamins and Supplements Break a Fast?

It depends on the supplement.

Some supplements contain calories, sugars, proteins, amino acids or other ingredients that mean they are better taken within your eating window rather than during a strict fast.

Certain vitamins are also better absorbed when consumed with food, particularly the fat-soluble vitamins A, D, E and K.

For this reason, you shouldn't assume that every supplement is best taken first thing in the morning simply because you're following intermittent fasting.

Instead, plan your supplements around your eating window and the individual product's directions for use.

How Do Willkins Supplements Fit Into an Intermittent Fasting Routine?

Intermittent fasting can reduce the number of meals you consume each day, making the nutritional quality of your eating window particularly important.

Supplements should never replace a varied, balanced diet. However, carefully selected nutritional supplements can complement your overall nutrition and active lifestyle.

Willkins has simplified its range around three advanced liquid formulas, each designed for a different nutritional purpose.

Willkins Ultra+ Multivitamin – Advanced Liquid Formula

Willkins Ultra+ Multivitamin provides more than 120 active ingredients in a convenient daily liquid formula, combining vitamins, probiotics, minerals, amino acids and a Super Greens blend.

It includes Vitamins A, C, D, E and K, all eight B vitamins and essential minerals including magnesium and zinc.

For people following intermittent fasting, a comprehensive multivitamin can provide a convenient way to complement nutritional intake during the eating window—particularly when eating fewer meals each day.

Because Ultra+ contains ingredients beyond simple calorie-free vitamins and minerals, it should be incorporated into your eating period rather than treated as a fasting beverage.

Willkins Collagen Marine 10.000 – Advanced Liquid Formula

Willkins Collagen Marine 10.000 provides 10,000 mg of hydrolysed marine collagen Type I and III per daily serving.

The formula also contains Vitamin C, Vitamins B5, B6, B7, B12 and D, together with selenium, silica and hyaluronic acid.

Collagen is a protein and therefore shouldn't be considered calorie-free fasting supplementation. If you're practising intermittent fasting, take your daily collagen within your eating window according to the product directions.

This makes Collagen Marine 10.000 easy to incorporate alongside breakfast, lunch or another meal depending on your chosen fasting schedule.

Willkins Joint Support – Advanced Liquid Formula

For people combining intermittent fasting with an active lifestyle, Willkins Joint Support provides a targeted liquid formula containing hydrolysed collagen alongside glucosamine, MSM and chondroitin.

It also contains Vitamins C, D and B12 together with selected additional ingredients.

As with the Willkins marine collagen formula, Joint Support contains collagen and should be taken during your eating window rather than during a strict calorie-free fast.

Can You Exercise While Intermittent Fasting?

Yes, many people combine exercise with intermittent fasting.

However, your response to fasted exercise can depend on the intensity and duration of the workout, your training experience and your overall nutrition.

A light morning walk before breakfast is very different from completing a long endurance session or demanding strength workout while fasted.

If you're training regularly, make sure your eating window still provides sufficient:

• Total calories
• Protein
• Carbohydrates
• Healthy fats
• Vitamins and minerals
• Fluids

Performance and recovery should not be sacrificed simply to extend a fasting window.

Common Intermittent Fasting Mistakes to Avoid

One of the biggest misconceptions about intermittent fasting is that eating less often automatically means eating healthier.

Common mistakes include:

• Overeating during the eating window
• Eating mainly highly processed foods
• Consuming insufficient protein
• Neglecting fruit and vegetables
• Not drinking enough water
• Exercising intensely without adequate fuelling
• Extending fasting periods too aggressively
• Ignoring persistent fatigue, dizziness or poor performance

A sustainable fasting routine should fit around your health and lifestyle—not make normal daily life unnecessarily difficult.

Who Should Be Careful With Intermittent Fasting?

Intermittent fasting isn't appropriate for everyone.

You should seek professional medical or nutritional advice before fasting if you are pregnant or breastfeeding, have diabetes or another condition affected by food intake, take medications that need to be coordinated with meals, have a history of eating disorders, or have other medical or nutritional concerns.

Children and adolescents should not undertake restrictive fasting programmes without appropriate professional guidance.

Frequently Asked Questions About Intermittent Fasting

How long should a beginner fast?

Many beginners find a relatively moderate overnight fasting period easier to manage. A 12:12 or 14:10 schedule can be a gentler starting point before considering a longer fasting window such as 16:8.

Is 16:8 intermittent fasting every day safe?

Many healthy adults use a 16:8 eating pattern, but suitability depends on individual health, nutritional intake, medication, activity levels and other factors. Longer fasting isn't automatically better.

Can I take a multivitamin while intermittent fasting?

Yes, but the timing matters. Many multivitamins are better taken with food, and products containing calories or additional nutritional ingredients should generally be consumed during the eating window. Always follow the individual product instructions.

Does collagen break intermittent fasting?

Collagen is a protein and provides amino acids and calories. Therefore, collagen supplements should generally be consumed during the eating window if you're following a strict fast.

Can I drink coffee while intermittent fasting?

Plain black coffee is generally used during fasting because it contains very few calories. Adding sugar, milk, cream or other calorie-containing ingredients changes this.

What should I eat when breaking a fast?

There is no need for a complicated "fast-breaking" meal after a normal daily fasting window. Focus on a balanced meal containing quality protein, vegetables or fruit, fibre-rich carbohydrates and healthy fats.

Is intermittent fasting better than a normal healthy diet?

Not necessarily. Intermittent fasting is one approach to organising food intake. Long-term health still depends heavily on diet quality, appropriate energy intake, physical activity, sleep and other lifestyle factors.

Intermittent Fasting and Supplements: Keep It Simple

Intermittent fasting doesn't need to make nutrition complicated.

Choose a fasting schedule that works with your lifestyle, prioritise nutrient-dense foods during your eating window, stay hydrated and avoid treating supplements as substitutes for a balanced diet.

If supplements are part of your daily wellness routine, timing them within your eating window can make intermittent fasting easier to manage.

Willkins focuses on three advanced liquid formulas: Ultra+ Multivitamin for comprehensive daily nutritional support, Collagen Marine 10.000 for a collagen-focused beauty and wellness routine, and Joint Support for people seeking targeted nutritional support alongside an active lifestyle.

Three formulas. Three clearly defined purposes. One simple approach to everyday supplementation.

Discover the Willkins liquid supplement range and find the formula that best complements your lifestyle.

Food supplements should not be used as a substitute for a varied and balanced diet and healthy lifestyle. If you have a medical condition, take medication, are pregnant or breastfeeding, or are considering substantial changes to your eating pattern, seek advice from an appropriate healthcare professional.