First of all I am so grateful to site/blogs such as this one. Without these firsthand testimonies I'm not sure what I would have done in seeking understanding of my situation. Thank you all for stopping to take the time to post your personal situations, look up information; the lists on this site are very informative, and comment and gently challenge each other; thank you.
I'm on a 5 yr journey of trying to understand what has happened to me. Since I was child I've had some adverse reaction; that I now understand to be some kindof 'sugar intolerance'. I can only ascertain that the symptoms got worst over the years and other debilitating symptoms/conditions have manifested since/latent onset. I kind-of acknowledged the symptoms in my mid to late 30s but thought eating healthy and being active, as I was an athlete most of my life, would enable my body to 'fix itself'. As the symptoms became progressively worst, numerous and multi-systemic (hypertension headaches, swelling headaches, severe hypoglycemic episodes, severe numbness in extremities; particularly at night, severe back-flank spasm, stroke like episodes, severe lethargy and lab blood work indicating some abnormal liver function test, to the most recent debilitating musculature-skeletal pain and fatigue, and etc...I realized I had to get help and information.
My research first led me to believe that I was gluten intolerant and had fructose malabsorbtion. Now, after 5 years of research, numerous and ongoing Dr. appointments, and trial and error with eating or rather not eating foods that caused the debilitating symptoms, it seems I don't fit in either classic category of fm or hfi. In short, I could tolerate some sugar and did not develop any connection/aversion to sugars until my late 30s. Currently and as I read through the above lists of foods and their sugar content, any foods with any trace amounts of fructose in particular and now seemingly any sugar, I cannot tolerate. I've tried them all (counting my spinach leaves, and cutting of the stem and veins) and I have been home-cooking everything. Just prior to thanksgiving, I recently cut out all carbs in addition to no fruits, vegies, corn or gluten products. (I did slipped during thanksgiving lol and paid for it.) I'm currently on a meat, cheese, water diet, and yes, my low weight is an issue. Up until college and perhaps my early 30s I could tolerate gluten but seemingly cannot now. I stopped drinking milk in my 20s. I have to cook my particular extra sharp cheddar cheese for at least 10 minutes so as not to have an allergic reaction.
It is becoming apparent to me that I have some progressive underlining issue going on. One of the sites I list below does suggest that people can develop antibodies to any enzyme and or food substrate, as is the case in Celiac disease. This includes (gluten, lactose, fructose, all sugars and even glucose/dextrose and or any of their derivatives and etc.).
Currently, I'm seeking official diagnosis of something; since at this point, my symptoms are not 'behaving' in accordance with current clinical understanding of fm or hfi. My research has given me some options as to why my situation seems so 'dynamic' and perhaps why many diagnosed as fm or hfi have such varying intolerance levels. Please dn't be put off by the medical jargon, just peruse pass it here and or at their respective websites, to grasp the general understanding of fructose and carb metabolism. I hope this info is helpful.
[Note: It seems that a person does not have to have a total absolute deficiency in all body system or even in a particular organ with regards to enzymes whether in the muscle, kidney, adipose tissue, small intestine and or liver; which might explain why some people have certain symptoms affecting certain systems and or organs and others do not.]
Dr. Tolan of Boston University/Usa has a adolase website that is very informative, as do Breakspear Medical Group in the U.k.:
Dr. Tolan's Adolase Lab at Boston University
www.bu.edu/aldolase/{Note: there are 3 adolase enzymes that aid in the metabolism of sugars; Adolase A, Adolase B, and Adolase C. All 3 are discussed in more detail at the website.}
HFI results from a deficiency of aldolase B activity in the liver, kidney, and intestine (7). The disease is inherited as an autosomal recessive trait and most parents of HFI patients and siblings who are carriers are unaffected and exhibit wild-type aldolase B activities (8). These repercussions of fructose ingestion are most dire for the newborn infant whose parents are unaware of the disorder and may coerce the persistent ingestion of fructose, making weaning during infancy the period of greatest risk. Undoubtedly some of the many cases of undiagnosed liver failure in infancy may be due to HFI. Those individuals that survive develop a permanent and powerful protective aversion to sweet-tasting foods (9). However, even later in life acute exposure of HFI subjects to the noxious sugar can lead to liver failure and death (10-12).
Aldolase B is the major aldolase isozyme in the liver and functions in both fructose metabolism, using fructose 1-phosphate as a substrate, and in gluconeogenesis, producing fructose 1,6-bisphosphate from the two triose phosphates, glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. In the absence of appreciable aldolase B activity, as in HFI patients, fructose challenge results in a rapid accumulation of fructose 1-phosphate in the liver, causing sequestration of inorganic phosphate. This drop in the intracellular phosphate pool activates AMP deaminase, leading to degradation of adenine nucleotides (13). The concomitant hypoglycemia is brought on by competitive inhibition of phosphorylase a by fructose 1-phosphate (14). These potentially serious manifestations of HFI arise from the inability of the body to degrade fructose and the subsequent impairment of glucose homeostasis (15). Click to see a body diagram of fructose metabolism in the normal and HFI patient.
The treatment for HFI is the exclusion of fructose, sucrose, and sorbitol (less than 40 mg/kg per day) from the diet (3) and results in complete alleviation of most symptoms and a normal life span (1). Older HFI subjects who adhere to a self-imposed fructose-restricted diet may continue to live undiagnosed and lead relatively normal lives. Complete exclusion of fructose is often difficult, however, and many HFI patients develop a syndrome of chronic fructose intoxication characterized by retarded growth, chronic liver disease, and hepatomegaly (3, 9, 15, 16). Furthermore, if not treated properly, these patients suffer episodes of hypoglycemia, general ill health, and strained relationships with family members due to their peculiar eating habits (17). Constant daily risk remains for HFI individuals due to the increasingly widespread use of these sugars as nutrients and sweeteners (18).
Breakspear Medical Group in the U.K.
www.breakspearmedical.com/files/documents/fructosemetabolism230910_AM_.pdf...
A deficiency or absence of fructose transporter proteins is one possible explanation for fructose
malabsorption and thus excludes fructose from anabolic and metabolic activities. Unabsorbed
fructose osmotically reduces the absorption of water and is metabolised by the normal colonic
bacteria (in the gut) to short chain fatty acids and the gases hydrogen, carbon dioxide and
methane. The abnormal increase in hydrogen can be detected with the hydrogen breath test, one
of the techniques employed at Breakspear to assess patients with suspected fructose malabsorption. Symptoms of malabsorption include,
but are not limited to, bloating, diarrhoea or constipation, flatulence, and stomach pain due to muscle spasms.
[Note:the hydrogen breath test cannot diagnose hereditary fructose intolerance]
THRREE HEREDITARY CONDITIONS THAT OCCUR WHEN FRUCTOSE METABOLISM IS COMPROMISED ARE...
hepatic fructokinase deficiency (essential fructosuria), hereditary fructose intolerance (HFI) and
hereditary fructose-1,6-bisphosphatase deficiency.
As its name suggests, hepatic fructokinase deficiency is a disorder affecting the fructokinase enzyme. The enzyme’s activity is either
decreased or disabled and fructose is not phosphorylated to fructose-1-phosphate. Fructose is
thus unable to enter the metabolic pathway. There are no toxic consequences to the liver or
kidney and individuals commonly do not present with any symptoms. The normal excretion of
fructose in the urine is only 1 to 2 per cent, or less, of an administered dose. However, in affected
individuals fructose excretion in the urine is 10 to 20 per cent. The remaining fructose that is
retained is most probably metabolised by adipose tissue via an alternative pathway.
A deficiency or a reduced functioning of the second enzyme in fructose metabolism, aldolase B,
results in HFI. When the aldolase B enzyme is deficient, its substrate, F1P, accumulates in the
liver and kidneys and has a variety of adverse effects.
The high levels of F1P inhibit enzymes of glycogenolysis (breakdown of glycogen via glycogen
phosphorylase) and gluconeogenesis (synthesis of glucose)leading to hypoglycaemia and its
associated adrenergic symptoms (sweating, shakiness, palpitations, anxiety), glucagonic
symptoms (hunger, nausea, vomiting, abdominal pain)and neuroglycopenic symptoms (including
impaired judgement, fatigue, ataxia, difficulty in breathing and impaired speech). The inhibition of
gluconeogenesis results in lactic acidosis as cells undergo anaerobic respiration (without oxygen)
in the absence of glucose. Lactic acid is the source of the muscle ache associated with vigorous
exercise and over-exertion. The liver will try to compensate by producing glucose from the short
chain fatty acids (SCFAs) acetate, propionate and butyrate. SCFAs are produced by anaerobic
bacteria in the colon acting on dietary fibre, such as pectin and various vegetable fibres. These
are then absorbed from the colon and enter the bloodstream, where some will remain, whilst
others are transported to the liver for storage. This rapidly depletes SCFAs in plasma, which can
be measured in the blood. Excessive fructose consumption may also lead to elevated levels of
fructose-6-phosphate in red blood cells, which, again, can be measured through a blood test.
Furthermore, as F1P accumulates, the stores of phosphate (ATP) are depleted and as a metabolic
consequence, uric acid levels increase. The lack of phosphate and ATP also interferes with many
other biosynthetic pathways including synthesis of protein, RNA, and DNA, cyclic AMP formation
and ammonia detoxification; thus HFI, although rarely, can become quite a serious affliction and
complete avoidance of fructose, sucrose, and sorbitol will be prescribed. For these reasons the
most acute conditions of HFI will most probably be identified and diagnosed early in life. However,
it is important to note that metabolic mishandling of fructose can occur at any level on some
continuum of severity.
...
[Note: check out the website for more details on the 3rd kind of fructose intolerance; hereditary fructose-1,6-bisphosphatase deficiency]
With excess fructose-1-phosphate in people with fructose intolerance, because there is a
deficiency of the enzyme to carry on making glyceraldehyde (aldolase), there is an inhibition of the
enzyme glycogen phosphorylase and therefore glycogen does not get utilised. There is also an
inhibition of fructose-1,6-bisphosphatase, which is responsible for breaking down fructose by
another route, and hypoglycaemia occurs. This can be profound. The liver will try to
compensate for this, and in doing so it breaks down the short chain fatty acids, acetate, propionate
and butyrate, and these become depleted. In addition, in the muscles, fructose-6-phosphate
levels rise. There is therefore a depletion in glycolysis in the muscles, as well as in the liver.
At Breakspear we are able to take measurements of the intermediary metabolism of fructose.
Apart from measuring plasma levels of SCFAs and red blood cell fructose-6-phosphate levels to
identify fructose intolerance, plasma lactate dehydrogenase activity can also be measured. This
enzyme is responsible for the conversion of lactate to pyruvate, and may be indicative of ‘mild’
liver damage due to elevated fructose stressing pathways in the liver.
We can measure:
•fructose-6-phosphate
•lactate dehydrogenase
•short chain fatty acids
Lactic acid dehydrogenase gives us an indication of
whether or not the liver has been involved in
this degradation.
Please check out these sites, i believe they break down the information sufficiently; even if the jargon might be a little distracting for some.
Each of these labs have noninvasive genetic and or blood testing for affirming and or diagnosing the presence of the various mutations or chemical evidence of fructose intolerance.
The various genetic mutations of fructose intolerance in particular, may explain why people have different degrees of intolerance, manifesting as different symptoms & in different body systems.
Lastly, this site suggest another possibility for sugar intolerance sufferers:
www.merckmanuals.com/home/childrens_health_issues/hereditary_metabolic_disorders/disorders_of_carbohydrate_metabolism.htmlDisorders of Carbohydrate Metabolism
Carbohydrates are sugars. Some sugars are simple, and others are more complex. Sucrose (table sugar) is made of two simpler sugars called glucose and fructose. Lactose (milk sugar) is made of glucose and galactose. Both sucrose and lactose must be broken down into their component sugars by enzymes before the body can absorb and use them. The carbohydrates in bread, pasta, rice, and other carbohydrate-containing foods are long chains of simple sugar molecules. These longer molecules must also be broken down by the body. If an enzyme needed to process a certain sugar is missing, the sugar can accumulate in the body, causing problems.
Glycogen Storage Diseases
Glycogen storage diseases occur when there is a defect in the enzymes that are involved in the metabolism of glycogen, resulting in growth abnormalities, weakness, and confusion.
Glycogen storage diseases are caused by lack of an enzyme needed to change glucose into glycogen and break down glycogen into glucose.
Typical symptoms include weakness, sweating, confusion, kidney stones, and stunted growth.
The diagnosis is made by examining a piece of tissue under a microscope (biopsy).
Treatment depends on the type of glycogen storage disease and usually involves regulating the intake of carbohydrates.
Glycogen is made of many glucose molecules linked together. The sugar glucose is the body's main source of energy for the muscles (including the heart) and brain. Any glucose that is not used immediately for energy is held in reserve in the liver, muscles, and kidneys in the form of glycogen and is released when needed by the body.
There are many different glycogen storage diseases (also called glycogenoses), each identified by a roman numeral. These diseases are caused by a hereditary lack of one of the enzymes that is essential to the process of forming glucose into glycogen and breaking down glycogen into glucose. About 1 in 20,000 infants has some form of glycogen storage disease....
[Note: please check out the site for more details on the specific glycogen storage disorders].
The bottom line for me is that based on my current understanding, there is no '1 size fit all' with regards to sugar intolerance and or hfi specifically. In addition, contrary to the seemingly repeated concept that hfi definitively manifests early in life is not all together absolute. There are several adult diagnosed cases and unknown numbers of adults undiagnosed but who have self restricted their diets from sweets and or particular foods that contain certain sugars or amounts of sugar. My personal situation suggests a progressive intolerance to sugars.
teri a.
