Fructosamine is a measure of your 2-3 week average blood sugar levels. It is used in diabetics to help monitor changes in glucose over time. However, many health conditions other than diabetes can affect fructosamine levels. Keep reading to learn more about high and low fructosamine levels and how to improve them.
What is Fructosamine?
Sugar (glucose) in the blood tends to stick to proteins. Fructosamine is formed when a sugar and a protein (usually albumin, but also globulin, or lipoprotein) are combined .
Similarly to HbA1c (glucose + hemoglobin), fructosamine is a measure of the amount of glucose in the blood. However, while HbA1c measures your 3-month average glucose, fructosamine reflects mean blood glucose over the previous 2-3 weeks. This is due to the shorter life cycle of albumin [1, 2].
The advantage of fructosamine over HbA1c is that it’s not affected by changes in red blood cells and hemoglobin caused by anemia, blood loss, or nutrient deficiencies .
That said, there are also drawbacks to using fructosamine. Temperature, vitamin C, bilirubin, urea, and total protein levels can all affect fructosamine levels. All conditions that increase or decrease albumin levels will also affect fructosamine [1, 3].
Fructosamine tests will not be a good measure of blood sugar control and should not be used in people who have [1, 3, 4, 5]:
- thyroid disease
- intestinal disease (protein-losing enteropathy)
- kidney disorders (nephrotic syndrome)
- liver disease
- increased immunoglobulin levels (especially IgA)
Fructosamine is used less often compared to HbA1c, mainly because it’s not standardized and it’s less reliable than an HbA1c test. In addition, because there is considerable overlap between the ranges of healthy people and diabetics, it can’t be used to screen for diabetes .
When is it Ordered?
If you’re diabetic, your doctor may test fructosamine to see how well you control your blood sugar levels. This test is especially useful to monitor short-term effects of changes in diet, exercise, or medication, without having to wait a couple of months to test HbA1c.
Fructosamine can also be useful in pregnancy when the body is going through week-to-week changes. Its shorter life cycle allows you and your doctor to track your blood glucose levels more closely .
Finally, fructosamine can be ordered instead of an HbA1c test in people who have anemia or abnormal hemoglobin due to genetic disorders such as sickle cell disease and thalassemia .
In non-diabetics with normal albumin, fructosamine levels normally range between 190 – 285 umol/L (micromols per liter) [1, 8].
Normal range may vary between laboratories.
In people with diabetes, fructosamine ranges from 210 – 563 umol/L. In poorly controlled diabetes, levels can be higher.
Levels tend to increase with age .
Causes shown below are commonly associated with lower fructosamine. Work with your doctor or another health care professional to get an accurate diagnosis. Your doctor will interpret this test, taking into account your medical history, signs and symptoms, and other test results.
1) Low Protein Levels
Fructosamine levels will be low when total blood protein and/or albumin levels are decreased .
Protein/albumin levels can decrease due to:
- Lack of protein in the diet (malnutrition) 
- Gut disease (protein-losing enteropathies) 
- Kidney disease (nephrotic syndrome), in which higher than normal amounts of protein are lost via the kidneys 
- Liver disease, where there are issues with albumin production 
- Hyperthyroidism (overactive thyroid), where there is increased protein turnover 
- Inflammation. Fructosamine is, much like albumin, a negative acute phase reactant. It decreases in those who are experiencing severe illness or injury 
Obese people have lower fructosamine levels than non-obese people, even among diabetics [14, 15, 16].
If you are overweight, this test may underestimate the average glucose levels in your blood.
Blood volume will normally increase in pregnancy .
While the absolute protein and albumin content stay the same, they become ‘”diluted”. That is why pregnant women have lower fructosamine levels .
The studies below look into associations between fructosamine levels and health conditions. Fructosamine doesn’t cause any of these conditions. Instead, underlying issues (such as frailty, infections, and inflammation) are responsible for both decreasing fructosamine and adversely affecting health.
In 477 women, low fructosamine levels were associated with an increased risk of hip fracture. This likely reflects frailty or malnutrition linked with lower protein levels .
In an observational study of 12k people, the ones with low fructosamine but high glucose levels had a higher risk of developing cancer later on, including prostate, colon, and lung cancer .
3) Heart Disease
In a study of over 11k people, low fructosamine increased the risk of heart disease over the next two decades .
In an observational study of 215k people without diabetes, those with low fructosamine levels had an increased risk of death. This was partly explained by the effect of smoking and chronic inflammation .
If your fructosamine is low, the most important thing is to work with your doctor to find out what’s causing your low fructosamine and to treat any underlying conditions. Your doctor will likely check your protein and albumin levels and may run further tests.
Losing weight if you are overweight may help. Fructosamine tends to decrease with increasing BMI [14, 15, 16].
Causes shown below are commonly associated with higher fructosamine. Work with your doctor or another health care professional to get an accurate diagnosis. Your doctor will interpret this test, taking into account your medical history, signs and symptoms, and other test results.
1) Elevated Blood Glucose
The main cause of high fructosamine levels is high blood glucose. Fructosamine will increase with your blood glucose levels in the previous 2-3 weeks .
Monitoring the trend of values will give your doctor more information than a single high value. If there is a trend of fructosamine increasing over time that means that you don’t have good control over your blood sugar levels .
In a study of 6 type 1 diabetic patients, long-term exercise over 8 months helped improve fructosamine and HbA1c levels. However, short-term, acute exercise increased both fructosamine and HbA1c .
Doctors should take exercise into consideration when testing fructosamine.
3) UV Exposure
Exposure to UV rays can increase fructosamine levels because it can increase the body’s temperature. This increases fructosamine production. In a clinical trial of 55 people sunbathing over 7 days, people who were exposed to UV rays had higher fructosamine levels than those who used sunscreen .
People with hypothyroidism have a decreased turnover of proteins, resulting in higher fructosamine levels .
In a study of 80 people, those with hypothyroidism had higher fructosamine levels than healthy people. The longer that a person has hypothyroidism, the higher their fructosamine levels get .
5) Increased Antibody Production
Fructosamine can increase when there is an increased amount of antibodies (globulin proteins) in the blood . This often happens with infections and inflammatory diseases.
When fructosamine is elevated in spite of normal glucose and albumin levels, your doctor will likely check your immunoglobulin levels [28, 29, 30].
6) Iron-deficiency Anemia
Studies suggest that people with iron-deficiency anemia may have significantly increased levels of fructosamine, probably as a result of increased oxidative stress [31, 32].
In AIDs patients, glucose adheres more readily to proteins. This causing fructosamine levels to increase. In an observational study of 75 people, the AIDs patients had higher fructosamine levels than healthy people .
In two clinical trials of 40 patients, the patients treated with glucocorticoids for asthma (prednisolone, budesonide) increased fructosamine levels .
The studies below look into associations between fructosamine levels and health conditions. Fructosamine doesn’t cause any of these conditions. Instead, underlying issues (such as high blood sugar, diabetes, serious illness) are responsible for both increasing fructosamine and adversely affecting health.
In an observational study of over 600 people, higher fructosamine levels were associated with depression .
2) Heart Disease
In two observational studies of more than 20k people in total, those with high fructosamine levels had a higher risk of heart disease, heart failure, stroke, and heart-disease associated mortality [36, 37].
3) Kidney Disease
In a study of more than 12k people, those with high fructosamine levels were more likely to develop chronic kidney disease over the next two decades compared to people with normal levels .
4) Recurrent Pregnancy Loss Risk
In case-control studies of 120 women, those who had recurrent pregnancy loss (RPL, two or more unexplained pregnancy losses) had higher fructosamine levels than women who did not have RPL. With each 20-umol/L increase in fructosamine, there was a three times higher chance of RPL .
In over 10k women followed over 5 years, higher fructosamine levels were associated with a higher risk of breast cancer in both premenopausal and menopausal women .
In a study of over 200 people, high fructosamine was associated with colon cancer .
In two studies of over 350k people, all-cause mortality (the risk of dying) increased with higher fructosamine levels [42, 36].
If your fructosamine is high, the most important thing is to work with your doctor to find out what’s causing your high glucose levels and to treat any underlying conditions. The additional lifestyle changes listed below are other things you may want to discuss with your doctor. None of these strategies should ever be done in place of what your doctor recommends or prescribes!
Fructosamine is a measure of your average glucose levels. Therefore, everything that helps decrease your day-to-day glucose levels will also help decrease fructosamine.
Eat foods with a lower glycemic index. Avoid processed carbs. These are foods that don’t cause spikes in your blood glucose. A meta-analysis of 119 studies showed that fructosamine is lower in people eating foods with lower glycemic index .
Eat more legumes. A meta-analysis of 41 trials suggests that non-oil-seed pulses, such as beans, chickpeas, peas, and lentils, all lower fructosamine levels .
Initial studies suggest that drinking herbal and oolong tea may help lower fructosamine levels in diabetics [45, 46].
Exercise regularly. Exercise improves blood sugar control and decreases fructosamine both in people with type 1 and type 2 diabetes [47, 23].
Talk to your doctor about the following foods and supplements. Initial studies suggest they may help decrease blood glucose levels and fructosamine:
- Aloe vera [48, 49, 50, 51]
- Alpha-lipoic acid [52, 53, 54]
- Garlic [55, 56, 57]
- Chromium [58, 59, 60]
- Magnesium [61, 62, 63]
Other supplements that can help decrease blood glucose include:
- Berberine [64, 65, 66, 67]
- Caffeine/Coffee [68, 69, 70, 71, 72, 73]
- Cinnamon [74, 75]
- Fenugreek [76, 77, 78]
- Fiber, such as glucomannan or beta-glucans [79, 80, 81, 82, 83, 84, 85, 86, 87]
- Flaxseed [88, 89, 90, 91]
Remember, always speak to your doctor before taking any supplements, because they may interfere with your health condition or your treatment/medications!