Reading food labels

Learning to read labels is an absolute requirement in buying foods for an HFI diet. Sugars are an especially difficult aspect to learn since they occur in so many different forms, especially in processed foods. If you do not recognize an ingredient on a food package, assume that it is prohibited until you know for sure what it is. Sugars and Sugar Substitutes, Fructose, Glucose, and Dextrose are examples of monosaccrides (simple sugars), which are sugar molecules that cannot be broken down further and remain a sugar. Polysaccrides (complex sugars) such as sucrose and lactose are larger molecules that are combinations of two or more sugar molecules. Honey is almost pure fructose, as are grape syrup, and other fruit juice sweeteners. Agave syrup contains high levels of fructose. Sucrose (table sugar) is derived from either sugar cane (or evaporated cane), sugar beets, brown rice, or dates and is a polysaccride consisting of glucose and fructose. Brown sugar is sucrose coated with molasses. Maple syrup or maple sugar are also mostly sucrose. Corn syrup and corn syrup solids are polysaccrides consisting of glucose and maltose. Although this combination should be tolerated, fructose is often added so the purity of the corn syrup has to be high to be tolerated. Not recommended. High Fructose Corn Syrup is being used extensively in the US because it is cheap to manufacture from corn syrup (which is mostly glucose). An industrial process converts the corn syrup glucose using an enzyme into a mixture of glucose and fructose in roughly equal proportions (about 55% fructose). The reason for doing this is that fructose is much sweeter tasting that the original glucose and the combination is a cheap sucrose replacement. Tariffs, quotas and subsidies on sugar imported to the US make the economics of HFCS even more attractive. Currently the US intake of HFCS matches the intake of table sugar in dry weight (about 60 lbs of each per year per person). As an exercise, the next time you go to a grocery store, pick up packaged foods and read the labels. You will be amazed at how many foods contain HFCS. Not only does the HFCS industry have a powerful political lobby to pass favorable laws, they must also have an extremely effective sales force for so many food manufacturers to incorporate it into products where its use makes no obvious sense. Chicory is used to make fructose and is not tolerated. Sorbitol is a sugar alcohol which the body converts into fructose. Dextrose is a simple sugar that is well tolerated. Glucose is a simple sugar that the body uses for energy. Maltitol is a sugar alcohol that may be tolerated depending on purity. Aspartame is an artificial sweetener that is tolerated, although some individuals report headaches. It is used in Equal, Nutrasweet, and Nutratase. Acesulfame-K is another artificial sweetener that is tolerated although its safety has recently been questioned. Saccharin is an artificial sweetener with questionable safety. It is no longer approved for use in Canada due to cancer concerns. Splenda or sucralose is a common sugar substitute. It is a chemically modified sucrose molecule that can be well tolerated depending on purity, although it can produce bowel issues if too much is consumed at once. Once you have memorized all of these sugars and know which to avoid and which are (or may be) safe to consume, you still have to master which foods contain which sugars. For example, bacon and ham can often contain maple sugar as an additive to cure and flavor the meat. Maple sugar contains sucrose which in turn breaks down to fructose.

Foods and Fructose

Fructose is generally contained in fruits, but actually occurs in a wide variety of foods. Not only are all fruits prohibited, you must also include those less obvious fruits such as melons, tomatoes, and coconuts on the HFI prohibited list. Many vegetables such as onions, corn, and peas contain unacceptably high levels of fructose and should be avoided. Thus, products containing onions or corn are excluded, including those that contain onion powder or corn flour. Wheat and all products containing wheat should be avoided. This is an extremely difficult requirement because of the number of products that contain wheat. Many products are labeled in a way that makes it less than obvious that wheat is included. For example, pasta packages may show semolina on the ingredients list. You must know that semolina is a type of wheat. Even foods labeled safe for Celiac Disease sufferers (who are intolerant of wheat gluten) are not usually safe for HFI use. Many of the grain flours which substitute for wheat may not have wheat gluten but do have significant fructose content. For example, brown rice and soy flours are not HFI safe. We have not found a satisfactory commercial bread substitute to date, but a combination of white rice flour and tapioca flour seems to make good bread that can be tolerated. Rice pasta is well tolerated, although you should avoid pasta made specifically with brown rice. Nuts and seeds are not generally tolerated as they all contain significant quantities of fructose. Soy products contain fructose and should be avoided. Most meats are well tolerated if not processed (ground and combined with other ingredients). Ham and bacon are not typically safe since they are sugar cured, although with some effort you may be able to locate a ham that uses only dextrose in the curing. Bacon is usually even more difficult although we have found that some stores carry salt pork sides that are essentially uncured, un-smoked bacon. Dairy products are generally well tolerated although you must read labels. Yogurts typically have sugars added.

A's Story

Our daughter's (will call her "A") story:

Our experience with A's HFI has led us to write this in the hope that others can benefit from our experiences. For example, one might expect that the word hereditary in HFI implies that the symptoms might be evident from birth. Although this may be the case for some, A's symptoms did not manifest in earnest until puberty. Although it may or may not be related to her condition, A cried a lot as an infant. Although colic is a catchall phrase for a baby that cries an unusual amount, her crying stood out as unusual because it lasted from mid-afternoon until well after midnight every day of the week for about five months. Nothing could comfort her so we took turns just holding her. Her pediatrician had the parents diagnosed as overwrought (which we were after months without a full night’s sleep) and did not take the complaint seriously. After her crying slowly reduced to more manageable levels she developed normally (although her crying as a young infant gave her rock hard abdominal muscles) and was a delightful child, although in her earlier years she still cried a lot more than other children her age. We now wonder if all of this crying might have been an early HFI clue, since irritability is a possible symptom of HFI.

The only other possibly related characteristic is that A has loose joints. After puberty she could easily bend her thumb to touch her wrist. Competitive swimming in grade school, junior high school, and high school took their toll on her loose joints. She had to have surgery on one shoulder to tighten her rotator cuff. The opposite shoulder is also loose, but she wants to avoid surgery on that shoulder as long as possible. She has also had major surgery on her jaws for TMJ as her jaws kept dislocating because of the loose ligaments.

It was during competitive swimming in the 9th grade that the first symptoms of HFI started to seriously manifest. At first the symptoms were those of low blood sugar. She actually blacked out briefly in the pool while swimming the 200 yd individual medley. Being a tough kid, she recovered enough to finish the race before the last finisher for that heat, but had to drop out of the meet after that effort. At the time, we knew that she was having more nutritional difficulties and started experimenting with different foods to address the low blood sugar. As it turns out, most of these experiments made matters worse because the obvious way to address low blood sugar is to ingest high carbohydrate foods, and being a swimmer, she needed the carbohydrates. Unfortunately, many of these foods made her feel much worse. Soon, she rapidly began feeling sick all of the time with frequent nausea, headaches, weakness, and shaking. She would wake up in the middle of the night vomiting. She did start to notice that sweet foods and fruits made her very sick, so she started avoiding these foods.

Another trip to the pediatrician, unfortunately, not the one who knew her, ran tests, but was unable to come up with a diagnosis. He decided it was acid reflux and gave her one of the well known antiacid pills. These made her even more ill and she stopped taking them within days. (Always carefully review medicine labels, both prescription and over the counter for added sugars. They almost all have them, even vitamins) We soon began to doctor shop to find one who could provide a definitive diagnosis. At this point, we were very concerned because she looked and felt ill all the time, was losing weight that she did not need to lose, (remember she was an athlete), had dark circles under eyes and had no energy. She was still trying to keep up with classes in her junior year in high school, many of them AP classes, and applying to colleges.

She saw multiple specialists in internal medicine, nutrition, endocrinology, and digestive disorders. One endocrinologist suggested that she might have Glycogen Storage Disease (GSD), an inherited disease with a least nine identified variations, most of which are very scary for a parent to contemplate. All of these variations result from genetic enzyme defects that prevent the body from properly utilizing carbohydrates. Ingesting carbohydrates causes these sufferers to accumulate byproducts and eventually cause liver or kidney failure. Although this tentative diagnosis was not ultimately correct, it did place us on the path of avoiding dietary carbohydrates as much as possible. A reduced carbohydrate diet did seem to start to have a positive effect. At a subsequent visit to this doctor, he abruptly dropped her as a patient stating that he could no longer help her and denied ever suggesting GSD as a possible diagnosis. We were stunned by this development, which we later learned was related to him being sued for malpractice. We were again back to square one for getting her condition addressed. All laboratory tests except for low blood sugar consistently came back negative.

It was apparent that we needed to look elsewhere for help. Our family physician, whom we had started with after the acid reflux diagnosis, was very supportive and helpful. He was amenable to assisting in getting A to a specialist in another city after the many failures in the local medical community. I tried to get her into an endocrinologist at Primary Children's in Salt Lake City, which ultimately did not happen. As a Registered Nurse who graduated from nursing school in Seattle, I went to one of my friends who still lives and works in Seattle for help. She gave me the names of several specialists with whom she has worked and respects. I called Children's Hospital and began a process that was again very frustrating. They have a wonderful team approach where they take a health history, request medical records and have various medical specialists, social workers, dietitians, and nurses review each case. They then decide if they will accept the patient and which medical specialist is appropriate. The call we received was not the one we wanted. They refused to take our daughter as a patient. We were devastated. A's health was declining and no one could figure out what was wrong. At this point, it was Christmas time and our older daughter was home from college. She hadn't seen her sister since August and was shocked at the change in her. She took me aside, and with tears in her eyes, asked if her sister was dying. That scared me even more. I called the RN at Seattle Children's again and begged her to have the team reconsider their decision, reiterated the seriousness of A's health and articulated that we were watching our daughter die before our eyes.

Why am I telling you this? Because you must know that if your loved one is so seriously ill and no one seems to take you seriously, you absolutely must be his/her advocate and keep trying to find someone who will listen. Luckily, they finally did reconsider and we were given an appointment with a gastroenterologist at Seattle Children's Hospital. We took her there for several days of testing. Among the tests done was a fructose tolerance test which is used to diagnose FI (but not normally HFI). The way that the test works is that bacteria that metabolize undigested fructose produce byproducts that include gaseous hydrogen. This hydrogen is then detected with a breath analyzer. The patient is made to drink high concentrations of fructose and the breath is then frequently analyzed for the presence of excess hydrogen. A’s test was stopped after the very first breath test because it was very positive for the presence of hydrogen. The fructose she had to drink for this test made her very ill for several days. At last we had a positive test result, although her symptoms did not match those of simple FI. Other tests need to be done to definitively diagnose HFI, which are DNA testing (currently have 70% - 85% detection rates), and liver biopsy testing ,which is the definitive diagnostic test. At this point the doctor felt confident enough to make the diagnosis without an extremely invasive liver biopsy. At last we had the disease diagnosed as FI. We were then sent to a dietitian for teaching regarding acceptable and unacceptable foods in a FI person. We left Seattle with a new sense of hope that our daughter would soon be on her way to recovery of her health

The lesson that we learned from this experience is that most doctors either lack the knowledge or are not willing to spend the time to diagnose difficult conditions. As a result shopping for the right doctor is critical. We had a diagnosis in less than a week, but it took three years to get there!

The treatment for HFI was to avoid all fructose containing foods, which was easier said than done. By the time that this was diagnosed, A was well into her senior year of high school, had undergone shoulder surgery during Christmas break the year before (another story with meds and foods) and was contemplating attending college across the country the following year. How do you allow your daughter with such drastic food restrictions to go across the country to college?! We had no idea how difficult it was going to be getting her healthy and finding foods that she could eat.

For several years we had probably taxed the capabilities of Google trying to find out all possible diseases that could explain A’s symptoms. Now we burned up the internet trying to find foods that A could safely eat. Learning to read labels is an absolute requirement in buying foods for an HFI diet.

What is Hereditary Fructose Intolerance?

Hereditary Fructose Intolerance

Hereditary Fructose Intolerance (HFI) is an autosomal recessive inherited disease (both parents are carriers but have no symptoms) that prevents the body from metabolizing fructose due to the lack of a key protein needed for the process. In severe cases, HFI can result in the death of undiagnosed individuals. Infants with this disease are usually diagnosed with failure to thrive and aren't diagnosed with this disease at all. If the disease manifests in infancy, the mortality rate is high. Amazingly, many older individuals with HFI are not diagnosed, but learn to dislike foods that are dangerous to them. Indeed, our own experience with the disease has shown us that few physicians know much about this disease because it is rare (about 1 in 50-200,000). This disease is often confused with the more common Fructose Intolerance (also called Fructose Malabsorbtion). The latter disease is associated with digestive symptoms such as bloating and diarrhea and does not have the potential to have life threatening consequences.

Although the two diseases, HFI and FI differ in severity, the treatment for both is the same. The sufferer should avoid ingesting fructose. As we will discuss later, this is easier said than done. Most FI sufferers tolerate small amounts of fructose, since the failure to absorb the sugar takes place in the gut. The symptoms of FI are caused by the presence of this unabsorbed sugar which feed bacteria whose byproducts in turn cause the discomfort. With HFI, the fructose is absorbed through the gut into the blood stream but cannot be utilized by the body, and accumulates as a waste product that rapidly overwhelms the body’s ability to eliminate it. A large dose of fructose can cause kidney and liver failure and even death in an HFI subject.

Heriditary Fructose Intolerance (also called Fructosemia) has the same relationship to Fructose Intolerance as Galactosemia has to Lactose Intolerance (LI). Galactosemia is a serious genetic disorder that produes very similar symptoms to HFI when milk sugars are ingested, while simple Lactose Intolerance, produces bloating and diarrhea like FI. While very unpleasant, neither FI nor LI typically have very serious long term health implications.

Since the solution to both FI and HFI is to avoid fructose, it might seem that this solution is simple. Although the solution is simple, the implementation of a fructose-free diet is far from easy. Avoiding all fruits does not even begin to address the diet. Fructose is contained in large categories of foods for which alternatives are not easily obtained. Consider that wheat, corn, peas, carrots, tomatoes, beans, and the vast majority of processed and snack foods contain fructose. Also consider that fructose is not always evident on food labels. Common table sugar (sucrose) is a compound sugar that is half fructose, so no foods with any added sucrose are acceptable. Other sugars are also be polysaccharides (compound molecule sugars) and must be avoided.

To make matters much worse for the HFI sufferer, high fructose corn syrup (a cheap sweetener derived from corn syrup) seems to have taken over the food industry. This sweetener can be present in almost any food. It is contained in almost all prepared or processed foods (including pickles, meat products, salad dressings, etc.). We have also made the mistake of believing a label that claimed a product was “sugar free” that actually contained a prohibited non-sucrose sugar in addition to an acceptable artificial sweetener. Honey is almost pure fructose.

The symptoms of HFI include nausea, fatigue, weakness, headaches, abdominal and muscle pain, and tremors associated with low blood sugar (which is a paradoxical effect actually caused by the accumulated fructose interfering with the body’s metabolism). The onset of these symptoms can be anywhere from a few minutes to an hour after ingesting a fructose containing food and can persist for several days while the body struggles to eliminate the accumulated waste from the body.

While this blog is intended primarily to address a lack of information about HFI, the dietary guidance also applies to FI sufferers (although the need to completely eliminate all fructose is not absolute for these individuals).