What does “Fall Back” mean when it comes to our health?

Daylight Savings Time is coming to an end this weekend, when we turn back our clocks and welcome an extra hour of sleep – at least for anyone who isn’t the parent of young children.   Along with that “Fall Back” comes shorter days, meaning fewer hours of weaker sunlight, as the earth tilts on its axis away from the sun. What this can also mean, particularly for those of us in the chilly northeast, is a drop in our vitamin D stores and a potential to develop a deficiency in this important vitamin.

Vitamin D, the ”Sunshine Vitamin”, is a fat-soluble vitamin that is manufactured by our bodies when sunlight hits our skin and is converted to a usable form of vitamin D by cholesterol.   Vitamin D plays a number of vital roles in our bodies, often behaving more as a hormone than a vitamin, and is largely unavailable naturally in most foods. As Winter approaches and we spend less time outside, the resulting lack of vitamin D in our bodies can have a pretty big impact on our health.  

Many people know that vitamin D is important for strong bones – vitamin D helps us absorb and use calcium, which is why most milk is fortified with vitamin D.  But did you know that vitamin D is one of the most important hormones and, along with thyroid hormone, is needed and used by every single cell in your body? Along with building strong bones, vitamin D is also necessary for:

Immune System Function

·       Gene Regulation

·       Increased Brain Power and Clarity

·       Lowered Cancer Risk

·       Fertility

·       Reduction of Inflammation

·       Improved Sleep

·       Fighting Depression and Anxiety

·       Reduced Asthma

·       Optimizing Metabolism and Weight Management

·       Reduced Risk of Heart Disease

In other words, vitamin D is hugely important!!  In colder climates, vitamin D deficiency is extremely common, with some studies showing up to 70% of the population having below-optimal levels.  Some surprising symptoms of vitamin D deficiency include fatigue, a general feeling of being ‘unwell’, depression and anxiety (“Winter Blues”), bone or muscle pain, stress fractures, cancer, diabetes, high blood pressure and autoimmune diseases.  Fortunately, it’s pretty easy to increase your vitamin D levels naturally.

Get Tested

A quick blood test can pinpoint where you stand in terms of vitamin D.  ‘Normal’ levels range from 25 to 137 nmol/L or 10 to 55 ng/ml, however for optimal health I recommend aiming for 100 to 160 nmol/L or 40 to 65 ng/ml.

Spend More Time Outdoors

This can be a tall order in the cold winter months, but 10-20 minutes spent outside at lunchtime (without sunscreen!) when the sun is at its strongest can help provide a boost.

Include the Right Foods

Though vitamin D is pretty scarce in most foods, there are dietary sources.  The current RDI for vitamin D is 600 UI per day, however during winter months with less sunshine, you should consider increasing to around 1,000 UI per day.   Good foods to try include:

·       Coldwater fish, such as cooked mackerel, cooked salmon or sardines (345, 360 and 250 IU of vitamin D, respectively)

·       Canned Tuna (236 IU)

·       Oysters (320 IU) and Shrimp (152 IU)

·       Whole eggs (20 IU vitamin D)

·       Fish Oil, such as cod liver oil, provides a whopping 1,360 IU of vitamin D per tablespoon.  There are many good options out there today that are lemon flavored and do not have a ‘fishy’ taste.

·       Fortified Foods – Milk, Cheese, Orange Juice. Though not a first choice, consuming fortified foods can help provide necessary dietary vitamin D.


Natural sources of any vitamin will always take first prize, but taking a vitamin D supplement is another easy way to optimize your levels.  Be sure that you are taking vitamin D3, which is the most usable and beneficial form of vitamin D for humans, and look for a supplement that doesn’t contain fillers, artificial colors or sugars.  Adding a Magnesium supplement may also help increase your body’s efficient use of vitamin D.

Hoping you all get to enjoy that extra hour of sleep – spend some of those precious daylight hours outdoors!


Koren Bradshaw, MS, CLC

Koren is a clinical nutritionist and certified lactation counselor passionate about functional nutrition and lifestyle education.