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Are there differences between normal reference ranges and optimal ranges?
Are there differences between normal reference ranges and optimal ranges?
Updated over a week ago

Yes. Even though you have normal ranges in your blood work report, chances are that they may not be optimal for overall physical health, performance and longevity— which is where optimal ranges come in. Optimal ranges are evidence-based ranges that are associated with the lowest risk of disease and mortality. Values for most of the tests fall well within normal range but they may still be combined with the high risk of diseases and mortality. This is the reason why you should always maintain optimal blood test range. For example, a lab’s reference range for vitamin D levels may be 20 to 80 ng/ml. While this is the range found in the lab’s testing population, this is NOT the range for optimal health. Rather, the reference range reflects that a large majority of the population does not have optimal levels for vitamin D. Scientific studies have shown that optimal ranges for Vitamin D are at least 40 ng/ml (100 nmol/L) up to 60 ng/ml (150 nmol/L) for optimal health¹. This is based on overwhelming evidence about the association between vitamin D and many diseases. The level of vitamin D at which 99% of rickets can be prevented is around 20 ng/ml (50 nmol/L). However, the risk of several other diseases, including multiple sclerosis, diabetes, and several types of cancer, are decreased when vitamin D levels are within the 40-60 ng/ml range. In fact, an even bigger benefit can be seen for cancer risk reduction at levels of at least 60 ng/ml².

What are normal reference ranges?

A reference range, sometimes called “normal values,” is a set of numbers representing the range of typical results. Each individual lab can establish their own reference range by calculating the range of values among a sample of “healthy” patients from within the population the lab serves. Since each lab can create its own reference range, these ranges can differ between labs and geographic regions. Differences in patient population, operating conditions, sample collection, criteria for “healthy” individuals, and environmental conditions can cause variation in reference ranges. Reference ranges can even change within an individual lab over time through ongoing re-assessment of their normal testing population.

Issues with normal reference ranges:

The so-called “normal” reference ranges in our lab test are based on the average of our population today, which include a large number of unhealthy people. In fact, if we consider our average population, for example the population in the UK, 40% of people have a diagnose of a chronic condition, 15% have a diagnose of two or more chronic conditions³ and tens of millions have a chronic condition that they don’t know yet, because they haven’t been tested. The majority of doctors still test patients “reactively”, that means they wait until the patient feel very unwell and then they test, they don’t proactively test. Doctors then look at these averages but these averages are not optimal. There are a number of limitations with these normal reference ranges, including:

• they’re very black and white and they don’t reflect how complex health is

• they usually don’t take into account how a value links to your risk of developing a disease or your life expectancy

• they don’t include the research on a large population about mortality and risks for disease.

• some of the population used to determine a range aren’t healthy

A lot of these limitations can be overcome using optimal references ranges.

What are optimal reference ranges?

Using scientific evidence and clinical guidelines, an optimal range is based on whether a range is linked to better health and longevity.

References:

1. Davis, W. Rockway, S. Kwasny, M. Effect of a combined therapeutic approach of intensive lipid management, omega-3 fatty acid supplementation, and increased serum 25 (OH) vitamin D on coronary calcium scores in asymptomatic adults. Am J Ther. 2009 Jul-Aug; 16 (4): 326-32

2. Garland, C. F. Gorham, E. D. Mohr, S. B. Garland, F. C. Vitamin D for cancer prevention: global perspective. Ann Epidemiol. 2009 Jul; 19 (7): 468-83.

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