Your essential collagen FAQ: what you really need to know

Collagen continues to grow in popularity for supporting skin, hair, joints and overall wellness - but with popularity comes confusion.

Below, we break down the most frequently asked questions about collagen, from the difference between marine collagen and collagen peptides, to safety concerns and how long results actually take.

Which is better: marine collagen or collagen peptides?

The short answer: they’re not opposites - marine collagen is a type of collagen peptide.

Collagen peptides simply refer to collagen that has been hydrolysed (broken down) into smaller, more absorbable units. These peptides can come from a variety of sources, including bovine (cow), porcine (pig) and marine (fish). However, these sources come with risk of metal/toxin contaminates.

Can collagen supplements cause weight gain?

There is no evidence that collagen supplements directly cause weight gain.

In fact, collagen is simply a protein. It contains fewer calories than many protein powders and may even help:

• Improve satiety, reducing snacking

• Support lean muscle when combined with resistance training

• Balance hunger hormones due to its amino acid profile

If weight changes occur, they’re normally linked to broader diet, lifestyle and calorie intake, not collagen itself.

Are collagen drinks good for skin?

Yes - collagen drinks are one of the most popular and well-studied routes for improving skin health.

Studies show that daily collagen intake can support:

• Improved skin elasticity

• Reduced fine lines and wrinkles

• Enhanced hydration levels

• Stronger skin barrier function

Liquid collagen is often absorbed faster than tablets and can also include complementary nutrients like vitamin C, hyaluronic acid or antioxidants. Consistency is key - most people begin to notice visible skin benefits in 6–12 weeks.

Can collagen cause cancer?

Current research shows no link between collagen supplementation and cancer.

Collagen supplements contain amino acids - the same building blocks present in foods like eggs and bone broth. These amino acids do not alter DNA or cell behaviour in a way that would increase cancer risk.

However:

• People with existing medical conditions should consult their healthcare provider before starting any supplement.

• Individuals with cancer undergoing treatment should always seek professional advice, as certain supplements may interact with therapies or nutritional plans.

In general, collagen is considered safe, non-carcinogenic and suitable for long-term use.

How long does collagen take to work on hair?

Hair growth is slow by nature, so collagen’s effects require patience.

Typical timelines:

• 4–6 weeks: Improved hair strength and reduced breakage

• 8–12 weeks: Noticeable shine, hydration and reduced shedding

• 3–6 months: Visible improvements in hair thickness and growth rate

This is because collagen supports the scalp, follicles and the production of keratin - the protein hair is made from. Results vary depending on age, diet, stress levels and hormonal health.

Are there any benefits of taking collagen at night?

You can take collagen at any time of day, but night-time supplementation has potential advantages:

• Supports overnight repair: Your body performs most of its repair and regeneration while you sleep.

• May improve sleep quality: The amino acid glycine, present in collagen, is linked to deeper, more restful sleep.

• Helps stabilise blood sugar overnight: Reducing energy dips or early-morning cravings.

• Convenient for habit-building: Many people find an evening routine easier to maintain consistently.

While benefits are similar regardless of timing, taking collagen at night can amplify its calming and restorative qualities.