Meet The Scientist Who Loves Lactoferrin

Meet The Scientist Who Loves Lactoferrin

Dr Hamid Merchant is Leapfrog’s consultant Pharmaceutical Scientist and is based at the University of Huddersfield where he teaches research and works with pharma companies to improve their products’ efficacy and safety. In 2021 he and his team published a meta-analysis of clinical trials that studied lactoferrin’s effects on Respiratory Tract Infections. The results were so positive that they made the British headlines.

Dr Merchant talks us through the rigorous standards he applied to analyse those trials and shares the results. He explains why lactoferrin is a useful tool in our arsenal to prevent coughs and colds this season and how it may reduce the symptoms and duration of infection if we come down with one. He also explains why not all lactoferrin supplements are created equal.

How did the meta-analysis on lactoferrin’s effects on Respiratory Tract Infections (RTIs) come about?

There’s a scientific ladder to conducting a trial. Normally in scientific research, we go step-by-step to understand what’s known about the product, what the safety is like, the ideal dosage, and what would be the best route to administer, as well as what scientific evidence has been published. Before conducting a new trial you have to know that it is adding knowledge and value to existing literature.

The meta-analysis we conducted was about reviewing those collections of RCTs (random clinical trials) already done, and we were lucky that there were several good-quality trials. We found more than 200 studies and then we sifted through those individual records and narrowed it down to nine studies. Out of those nine, only six could be used for statistical analysis.

How did those six studies stand out, and what evidence did they provide about lactoferrin’s efficacy?

The beauty of the analyses was that these were studies from different parts of the world – Japan, the US, Canada, Australia and China. The other good thing about the studies was that they had different age populations from babies and children to the very frail and elderly. So, we were able to see the effect of lactoferrin in a very wide age group, and the number of respiratory infections prevented.

The major aspect of our meta-analysis was if lactoferrin prevented the occurrence of RTIs. The secondary objective was to see if somebody got an RTI and if they had a quicker recovery. We found the number of respiratory incidences happening in the lactoferrin group was significantly lower, and in the studies that looked at symptom recovery – how people recovered if they already had an infection – the studies confirmed that people who had the lactoferrin intervention had better recovery.

What is the mechanism of action behind lactoferrin? How does it prevent or reduce the duration of a cough or cold?

What lactoferrin does is it provides a multi-prong approach to immune system regulation. First, it can bind to bacteria and viruses and prevent entry into the cell. It attaches itself to the membrane transporters and preoccupies those gates – like a security guard – so the viruses and bacteria can’t go through. That’s the first defence: it prevents cell entry to the invading organism. Secondly, it initiates a cascade of reactions. We then have cellular immunity and antibody response which comes as a team to mount a response against the infection. Lactoferrin works as a team with cellular immunity and antibodies.

Lactoferrin is naturally found in fluids in the body, in the eye, mouth, and nose secretions for example so it can be available at the point that the pathogens come in. It’s a molecule which is naturally present in our body system with a modulatory role – it initiates a cascade of reactions for other molecules to be released and do their specific jobs.

How does it help with inflammation?

Lactoferrin is an immunomodulatory substance – so if the immune system is weak it empowers it, or if the immune system is hyper-reactive, then it lowers it. It’s a very important mechanism. Mother Nature has created different body systems – the body has got pro cellular mechanisms which can initiate a cycle and the body has other signals which can inhibit the cycle. For instance, we all get inflammation when we get an injury – a mechanical injury or an infection – and inflammation is good and helps fight it. But when the inflammation goes out of control, then the body’s anti-inflammatory processes kick in. In some chronic inflammatory diseases, that anti-inflammatory mechanism doesn’t kick in as much as the pro-inflammatory mechanism. If the body is firing too much cytokine response, then lactoferrin could be able to mediate.

If one has already caught a cold, what can lactoferrin do?

Lactoferrin initiates a cascade of reactions and promotes the immune system to secrete some of the chemokines and cytokines – chemical substances – that react with the virus or bacteria. What lactoferrin also does is regulate the hyper-inflammatory process; for example, you get a sore throat because your glands get inflamed, but if you were taking lactoferrin supplements before you caught a cold, then you might not get that serious swelling or inflammation. But if you take lactoferrin once you’ve caught a cold, it will try to mediate that inflammation, and you might take some anti-inflammatory therapies like ibuprofen or paracetamol too. It does have a role in mediating inflammation at that stage and is a good adjunct for post-infection mediation as well.

If our body makes lactoferrin naturally, why do we need to supplement?

Maintaining a constant concentration of lactoferrin 24/7 in those molecules can be a challenge. Lactoferrin is a molecule which can function genetically in any microorganism, which is why it’s easy to take lactoferrin as a supplement. It’s a molecule classed as safe as a nutritional supplement across every age group and for those with health conditions (even pregnancy). This gives lactoferrin an edge.

“The meta-analysis revealed a significantly reduced odds of developing respiratory infections with the use of Lactoferrin…Lactoferrin may also have a beneficial role in managing symptoms and recovery of patients suffering from RTIs and may have the potential for use as an adjunct in COVID-19”

Lactoferrin reduces the risk of respiratory tract infections: A meta-analysis of randomized controlled trials (2021)

Were you surprised by how positive the results of your meta-analysis were?

It’s difficult with studies to get a clear black-and-white outcome and very often there are mixed findings. But with lactoferrin there was a clear demarcation, so when we looked at the ratio between the control and the intervention group it was very clear. Statistically, the difference was significant, which is why it was so easy to conclude the findings.

What do you think is the future for lactoferrin within the health and wellness sector?

One magic ingredient normally has the capacity to go up to a point, so what we need to look at are the constituents of the immune system. So lactoferrin will find a place in the immune support supplements range, alongside Vitamin C, Vitamin D and Zinc. To get the best synergy you need all the compounds to support the immune system, so consider lactoferrin in combination with Vitamin C, vitamin D and Zinc.

Which sounds like the formulation for Leapfrog IMMUNE! Lactoferrin + Zinc + Vitamin C. Why should we take these supplements and how much of these nutrients should we be taking?

There are many other viruses aside from COVID running around in the winter months. Other pathogens went down the priority list as we’ve dealt with COVID, so our antibodies think that they are not a threat and are not going to come back. Minor exposure to common pathogens primes your body. Your body may be primed and boosted to respond to a particular pathogen – COVID – which means that the ability to fight off other infections goes down. And that’s in fact how our body uses its resources – if it’s not required, the body will not prioritise it. So that’s why people should start taking supplements at the recommended daily dose.

It’s important that people know they don’t need to take lots of quantities, they just need to take the recommended daily dose. With regards to vitamin D, the Public Health England advice is very clear that in the winter months you need it, and that the recommended supplement dose is enough.


In Leapfrog we have the recommended daily dose of vitamin C and zinc in two tablets, and 250mg of lactoferrin is widely regarded as an acceptable dose for prevention. What else should we consider when supplementing with lactoferrin?

People should understand lactoferrin is a biomolecule, and lots of biomolecules have a complex biological structure with a 3D configuration. This shape is very important for latching into the receptor. Many chemically treated products, and the way the lactoferrin is extracted from the milk, can affect the lactoferrin’s activity, so not all products in the market would be equally effective. There are lots of supplements available, but because lactoferrin is a nutritional product it doesn’t go through the same level of scrutiny as medicine goes through. Some lactoferrin molecules may not work as well as other lactoferrin molecules.

Our lactoferrin suppliers can perform a 3D crystal of lactoferrin because it is so pure!

Yes, always buy products from reputable sources. Lots of online materials available can be dodgy! They need to have traceability of where the materials are coming from.

We chose to make Leapfrog chewable as it’s more effective that way. You’re a believer in oro-dispersible tablets in general, why is that?

When a baby is born their guts are not very well established, so if the baby is thirsty, we don’t give them water we give them milk. If it comes from the breast it is sterile and doesn’t harm. Their intestines are not very well developed, they are leaky and can absorb anything coming out from the milk. Milk contains lots of substances – lactoferrin, immunoglobulins, pre-prepared antibodies, immune memories and lots of fantastic stuff which I can’t absorb, and you can’t absorb as an adult because our guts are not leaky, they are tight.

The babies can absorb them until their guts mature and they start weaning and eating solid food. Biomolecules are then destroyed by the stomach acid and they are too big to get absorbed anyway. So, these molecules are best absorbed through your oral cavity. Also, lactoferrin is not corrosive to the oral mucosa and is in fact found naturally in your saliva so delivering where the lactoferrin is normally present makes sense (plus there are lots of absorptive areas around your cheeks and under your tongue). I believe oro-dispersable tablets – like a chewable tablet that is kept in the mouth – would give the best chance for lactoferrin to be absorbed.

Read Dr Hamid Merchant’s meta-analysis:


Lactoferrin reduces the risk of respiratory tract infections: A meta-analysis of randomized controlled trials (2021)