Hereditary Fructose Intolerance (HFI) UK
Raising awareness of HFI among healthcare and allied professionals, and support to individuals with HFI and their families.
HFI Information and Support
This website is currently under construction, please bear with us.
If you are looking for more information or need support, please get in touch via the contact button above or email us at:
What is HFI?
Hereditary Fructose Intolerance (HFI) is an inherited condition caused by a deficiency of the enzyme Aldolase B, which is normally found in the liver, kidneys and small intestine. Someone with HFI is born with it. It usually doesn't show up until a baby is weaned onto solid foods.
When does HFI show itself?
A person with HFI is affected from birth, meaning their dietary needs must be addressed right away. Symptoms often appear during bottle feeding if the formula contains fructose, or more frequently when solid foods like fruit, vegetables and other sugary foods are introduced to the child's diet.
What are the first symptoms?
Fructose, Sucrose and Sorbitol given to a child with HFI will result in a baby being very unsettled, frequently crying or screaming. It's often mistakenly attributed to "colic".
Diarrhoea and gut pain are common symptoms. Ingestion of these sugars leads to low blood glucose, causing a baby to become pale and drowsy.
How is HFI acquired?
HFI is an inherited condition. It is a mutation of a recessive gene. This means that both parents will carry one mutation copy but will not have the condition themselves (unless one of them actually has HFI). If both parents are carriers, there is a 1 in 4 chance of a child having HFI.
How often does it occur??
It is estimated that 1 in 15,000 children will be born with HFI. As it is rare, the diagnosis is often missed. It is vital that health professionals are made aware of the condition and symptoms. Doctors are told that "If you hear hoofbeats, it's probably a horse". We say "If you hear hoofbeats, it could be a zebra".
What happens if it's not recognised?
Ingestion of Fructose, Sucrose or Sorbitol causes hypoglycaemia - abnormally low blood glucose levels. A child may be classed as 'Failure to Thrive'. Accumulated fructose acts as a toxin/poison and causes potential lasting damage to the liver, kidney and small intestine. If not recognised, this can result in death.
What happens in the body when fructose is ingested?
What happens if it's not recognised but the person survives?
Individuals with HFI develop a strong aversion to sweet tastes, which can be a lifesaving response. Continuing to consume unsafe sugars may cause liver and kidney damage. HFI may be detected by dentists when treating adults who have no dental decay, as the absence of cavities can be an indicator of the condition.
How is HFI treated?
There is no treatment as such yet, but someone with HFI can stay healthy and well as long as they stick to a diet free of Fructose, Sucrose and Sorbitol. This diet is our lifesaver, but is often misunderstood, even by dieticians. The common concept of a "healthy" diet is poisonous for individuals with HFI.
Who is behind the HFI charity?
The charity was founded by two adults with HFI - Bill Armstrong and Carol Westwood, and a parent of a young child with the condition. It is VITAL to raise awareness of HFI to save lives and prevent unnecessary suffering caused by misdiagnosis or missed diagnosis.
Thank you for your patience during this site's construction.
Whilst we build this website, you'll find a little light reading in the blog section. It's a rough timeline account of the experiences that one of the charity founders had growing up with undiagnosed HFI, written as musings. Grab yourselves a cuppa and find out what HFI looks like in reality!
HFI Blog
Recent article from Rare Revolution magazine
Recent media
Read our recent contribution to Rare Revolution magazine. Click the 'Learn More' link below
Hereditary Fructose Intolerance (HFI) UK
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