Someone with HFI who has eaten or drunk something containing fructose, sucrose or sorbitol will start off feeling nauseous. They may then vomit, have stomach pain, feel shaky and tired. Their blood sugars will drop and they become hypoglycaemic. Most people with HFI will not like the taste of sweet things and will probably refuse them. This is important if it is noticed in a baby or child.

Ideally you will be under the care of a specialist metabolic paediatric or adult service. You should get regular health checks from that service, and request access to a specialist metabolic dietician.

HFI support is in the process of collating recipes for a book that can be used by those with HFI and given to friends, who are often at a loss as to what food to prepare. There is an as yet unpublished collection of recipes from the specialist dietetics department at Addenbrooke’s hospital, Cambridge, UK.

Whilst there seems to be some slight variation between tolerance for some foods amongst people with HFI, it is important to remember that “tolerated” is not the same as “safe”. There has been some research to suggest that the individual mutations for HFI (there are 18 identified so far) may affect people slightly differently, but there are no gradings such as “mild, moderate” etc. Someone with two HFI gene mutations will have the condition. 

The vaccination schedule can vary from one country to another. Currently in the UK, the only vaccine that is not recommended for a child with HFI is Rotavirus. All others are safe and recommended.

If it has only been a small amount of fructose, offer a drink of milk. This should settle any nausea and reverse any hypoglycaemia. If it was a large amount or your child is vomiting, listless or ‘floppy’, do not hesitate to go to A&E. Your specialist paediatrician should have suggested or prescribed a dextrose for use to reverse low blood sugar. If unsure, always call and speak to a doctor. Make sure they are aware of a HFI diagnosis… Keep fluid levels up by offering drinks of water.

The only safe paracetamol product for babies and young children is paracetamol in suppository form. All paracetamol preparations for children to have by mouth are unsafe for a child with HFI. Please discuss with your paediatric metabolic specialist or specialist pharmacist.

Antibiotics for a child with HFI should only be given after specialist advice from a doctor or pharmacist who will check for safety. Always check the ingredients list on all medication and do not be afraid to question anything.

Schools must be made aware if a child has HFI and the measures they will need to take to ensure the child’s safety. We have a leaflet specifically for schools and nurseries. See the Downloads & Information section.

Fluoride, as with any other supplement needs checking that it does not contain any fructose, sucrose or sorbitol. Make sure that your dentist is aware of this.

There are some safe toothpastes but as ingredients can change, always check the labels. Any toothpaste with saccharine or aspartame is safe. Sorbitol is not.

Yes! Absolutely you can, but each individual for checking what they eat.  It is a case of checking with a restaurant or food venue whether there is fructose or sucrose in certain food – ideally in advance. Sugar is not an allergen and it is currently not a requirement for food establishments to alert you to the presence of fructose or sucrose in foods. However, a good venue will let you see the list of ingredients. Always ask for the ingredients list rather than an allergy or intolerance list and check for yourselves whether the food is safe.

Yes! Absolutely you can, but each individual for checking what they eat.  It is a case of checking with a restaurant or food venue whether there is fructose or sucrose in certain food – ideally in advance. Sugar is not an allergen and it is currently not a requirement for food establishments to alert you to the presence of fructose or sucrose in foods. However, a good venue will let you see the list of ingredients. Always ask for the ingredients list rather than an allergy or intolerance list and check for yourselves whether the food is safe.

Please refer to our diet sheet… unprocessed meat, fish, seafood, dairy products – e.g. milk, plain yoghurt, cream and eggs do not contain fructose.  White flour products e.g. bread and pasta are preferable to wholewheat. Check for any added sugars. Some breads can be sweet. A small amount of dark green vegetables (prepared with stems removed) are generally low in fructose – refer to diet sheet.

A child with HFI will start to show symptoms during weaning, generally whenever fruit is first introduced. Some infant formula milks contain sugar too, so sometimes symptoms will occur before weaning. A child with HFI who is given unsafe sugars will be screaming, vomiting, having diarrhoea after each time they are given the unsafe food. They may get sleepy if they become hypoglycaemic, and will need medical intervention.

No. If someone has HFI they are born with it, and will have had adverse reactions to fructose, sucrose and sorbitol all their lives. Fructose Malabsorption is a different condition, and management is completely different. It is important to get an official diagnosis of HFI to ensure safe diet, medications, hospital stays, etc.

The first signs that you’ve accidentally consumed fructose, sucrose or sorbitol will usually be nausea. Someone with HFI will start to feel sick, maybe get a headache, just generally feel unwell. They will then probably go on to vomit.  Most people find that a glass or two of milk will settle the nausea. Most people with diagnosed HFI will have been advised to carry dextrose tablets or gel with them at all times. This will safely reverse any hypoglycaemia (low blood sugar) that has occurred.

Yes. Lactose, in milk and dairy products is safe, as is dextrose and maltose.  Glucose has been used a lot in the past as a sugar alternative for HFI, however there is ongoing research into whether some people convert some of the glucose to fructose via the polyol pathway. Glucose, galactose, lactose, maltose and starch

• Food labelling is difficult for HFI. Avoid anything that says Fructose (fruit sugar)
• -  Disaccharide (sugar, table sugar, sucrose
• -  Invert
• -  Sorbitol (E420)
• -  Isomalt (E953)
• Fructose, fruit sugar, laevulose
  sugar, sacharose, sucrose, cane sugar
• Beet sugar, powdered sugar, candy sugar, caster sugar
  syrup, honey
• Isomaltulose
• Palatinose

Some vegetables are lower in fructose than others, however this can vary depending on the variety of vegetable, when and how it has been harvested, how it has been stored, and other factors. Please refer to our diet sheet here… The only fruit that is permissible in small quantity is rhubarb and olives.

Vit C. Folate.  Most specialist metabolic centres will regularly check for and vitamin deficiency.

As a carrier you will not have HFI. Any children that you have will have a chance of having HFI if your partner is also a carrier. For this reason, if you know you have HFI, it is precautionary for your partner to be tested for the HFI carrier gene as well. Should both of you carry the HFI mutation, your newborn can be tested at birth, and be given a safe diet from the outset should they have HFI.

• Glucose
• Galactose
• Lactose
• Maltose
• Starch
• Grape sugar
• Dextrose
• Maltodextrine
• Glucose Syrup
• Corn-
• Rice-
• Barley
• Malt syrup
• Starch
• Inulin
• Oligofructose/fruco-oligo saccharide