Dealing with Depression and Seasonal Affective Disorder (SAD)

Dealing with Depression and Seasonal Affective Disorder (SAD)

If you’re affected by this debilitating condition when winter closes in and the dark clouds of gloom descend – it’s important to gather together as many coping strategies as you can to survive the dark days.

Depression can be mild, moderate or severe and includes SAD which is a form that commonly occurs in winter affecting around 2 million people in the UK and Ireland alone, but also has a significant impact on the global population.

Seasonal changes may dramatically affect the mental health of some while for others there may only be subtle changes in mood and behaviour.

In its mildest form, depression can mean just feeling ‘flat’ with little motivation to get on and do things.

You can still function but everything feels like a chore and less worthwhile. In its most severe form, depression can take away the will to live and drive a person to suicide.

The latter form is known as clinical depression and generally requires medical treatment.

Depression is not just about feeling sad or miserable there are a number of other distressing symptoms which can affect many people depending on how severe the depression is.

  • Lethargy and difficulty in sleeping
  • Loss of appetite
  • Inability to concentrate
  • Poor memory
  • Self-harming
  • Loss of interest in pretty much everything
  • Inability to make decisions
  • Overwhelming sense of loneliness
  • Feeling alienated from everyone
  • Fear of the future
  • Feelings of guilt
  • Frustration with self
  • Inability to sense pleasure
  • Suicidal thoughts
  • Lethargy and sleep problems
  • Irritability and intolerance to stress
  • Anxiety and inability to cope with day to day life
  • Low sex drive
  • Carbohydrate and sugar cravings


Possible Causes

Although life circumstances or even biological influences may trigger depression, there is no general consensus as to the exact cause of depression.

Some believe it is due to a chemical imbalance in the brain, but in fact it is much more complex than that.

There may be many contributing factors that play a part such as: nutritional deficiencies, genetic vulnerability, food sensitivities, medications, low blood sugar, low thyroid function, faulty mood regulation by the brain, lack of exercise, stress and lack of sunlight.


Nutrient deficiencies

Decades of research have shown that the chemistry and function of the brain is influenced by diet.

Because so many nutrients play an important role in brain function and general cell health, virtually any deficiency can result in depression which is why it is so important to eat a healthy balanced diet.

The main nutrients identified in helping to alleviate depression include the B vitamins particularly B3, B12, folic acid and B6; vitamin D, the minerals iron, zinc and magnesium – phosphatidyl serine, essential fatty acids (especially the omega-3 family) and the amino acids tryptophan, tyrosine, and glutamine.

According to some studies vitamin C deficiencies can affect brain function – furthermore a lack of antioxidants is also shown to be detrimental to cognitive health.

One particular antioxidant that is emerging as a potential therapeutic tool for the treatment of depression is Alpha Lipoic Acid.

Research has found that this vital antioxidant increases insulin sensitivity which plays a role in the brains ability to increase serotonin synthesis, elevating feelings of happiness and wellbeing.


Low blood sugar (Hypoglycaemia)

Hypoglycaemia is an abnormally low level of glucose in the blood and is a factor underlying most depression.

In mild depression (or low mood) it may be possible to alleviate fluctuations in mood simply by balancing blood sugar levels.

In more severe depression it is worthwhile taking measures to control blood sugar balance whilst investigating other potential contributory factors.


Food sensitivities

Many people have chronic food or chemical sensitivities that can potentially bring about a whole range of symptoms including anxiety and depression.

Specialised laboratory tests are available to identify food allergies and intolerances; alternatively with the help of an experienced practitioner an elimination diet can help to isolate any problematic foods.



Control mechanisms in the body are geared towards counteracting the everyday stresses of life, however, if stress is extreme, unusual, or long lasting, these control mechanisms can be overwhelming and quite harmful.

Long-term stress can impact the body by supressing the immune system, slowing down the digestive system, depleting the body of nutrients and impeding the body’s rate of repair.

Stress can also affect thyroid, pancreas, liver, kidney and brain function.

Mental and emotional problems such as depression, comfort eating and anxiety are likely to become prevalent.

Other stresses come in the form of poor dietary choices including the use of sugar and stimulants such as caffeine and alcohol, as well as a lack of exercise. Diet, exercise and relaxation techniques are all important points to address when trying to reduce stress.


Thyroid Function

The link between thyroid function and psychiatric conditions, particularly mood disorders has long been recognised. Both excess and insufficient thyroid hormones can result in mood abnormalities including depression.

Studies have established that individuals with thyroid problems especially sub-hypothyroidism are more prone to develop depressive symptoms. Managing stress, regular exercise and healthy, balanced food choices are vital in the support of thyroid disorders.


Lack of full spectrum light

SAD appears to be caused by light deprivation. Cold weather drives people to spend more time inside and the days are shorter overall giving us less access to daylight.

Sunlight is a visible electromagnetic energy which has a significant impact not just on our bodies but also has a profound effect on our moods, making us feel warm, cheerful and optimistic about life.

Humans have evolved under sunlight and have not adapted well to artificial lighting. Few people work outside and many of us live, travel and work in conditions where we are shielded from natural daylight.

Unsurprisingly, SAD is particularly prevalent in people living in the Northern hemisphere with symptoms usually starting in September and October. However, those living 30 degrees from the equator where days are long and hot are rarely affected.

Lack of sunlight can be detrimental to health in many ways and for the increasing number of people suffering from the winter blues it can be hard to escape from the misery of fatigue, lethargy, sleep problems and cravings for carbohydrates which may exacerbate weight issues.

Sunlight is often overlooked when considering triggers for depression and can be thought of as a missing nutrient especially as we are so reliant on it to manufacture vitamin D through the skin. Nevertheless researchers have linked low vitamin D status with depression, which sheds some light on why SAD occurs during winter.

Reduced levels of important mood raising neurotransmitters such as serotonin have also been suggested as a contributing factor in SAD. The many complexities of brain chemistry mean that any imbalance in neurotransmitters can affect brain function and subsequent moods.


Areas of the brain that affect mood

New technology has allowed scientists to identify key areas of the brain that play a role in depression; these include the amygdala, the hippocampus and the thalamus.

In fact research shows that in some depressed patients the hippocampus is smaller than those who are not depressed and the more bouts of depression these patients had, the smaller the size of their hippocampus.

Interestingly, what has since been found is that as new neurons grow in the hippocampus, strengthening nerve cell connections and improving the exchange of information between nerve circuits – mood improves.

Scientists are exploring the possibility of developing medications that promote neurogenesis (new nerve growth).

In the meantime making sure you maintain good levels of brain supportive nutrients may help to support nerve growth and function.


Nutrition Advice

Overall brain support will help reduce many of the symptoms of SAD and depression.

The importance of a healthy balanced diet cannot be understated; let’s take a look at some vital nutrients that could make a difference.


Alpha Lipoic Acid (ALA)

ALA is a really powerful antioxidant able to scavenge free radicals – these compounds cause harmful chemical reactions that can damage all cells, including those in the brain.

Brain inflammation is one of the key factors implicated in depression.

Because ALA possesses such powerful antioxidant activity it can offer a uniquely efficient protective mechanism against the damaging effects of inflammation and toxicity in the brain.

Unfortunately throughout your lifetime your brain acquires inflammation and wear and tear that needs good quality nutrition and lifestyle intervention.

If you’re determined to reduce the symptoms of SAD, ALA could be a worthwhile supplement choice.


B Complex Vitamins

Research evidence suggests that collectively the B vitamins are essential for optimal physiological and neurological functioning.

Many studies have focussed on the positive effects of B vitamins on brain health and their ability to reduce symptoms of low mood and depression.

Not only this, the B vitamins are also involved in every aspect of energy generation within the cells, vitally important especially in the winter months when energy levels often slump, especially for those suffering from SAD.

In one trial, a group of 60 adults diagnosed with a spectrum of depressive disorders were randomly given either a vitamin B complex or a placebo.

After a 30 and 60 day follow up the participants given the B complex showed significant and continuous improvements in depression and anxiety compared to those given the placebo.

A healthy balanced diet that includes whole grains, fish, poultry, fruit and vegetables – particularly leafy greens, should provide sufficient B vitamins.

Those with dietary restrictions or digestive issues may benefit from a vitamin B complex supplement.


Vitamin C

Often overlooked when it comes to brain health, but shouldn’t be because vitamin C is particularly important for the production of neurotransmitters in the brain which are associated with anxiety and low mood. It also plays a key role in preventing an increase of cortisol, a hormone the body releases in response to stress.

Accumulating data has shown that vitamin C is one of several nutrients that can enhance neurocognitive function and may offer therapeutic benefits for those that suffer from depression. It seems topping up with vitamin C may help you to cope better with the demands of daily living.


Essential Fatty Acids (EFAs)

A meta-analysis of a number of studies confirms the benefits of omega 3 EFAs and their potential for the treatment of major depressive disorders.

Omega 3s which are naturally found in fatty fish, grass fed lamb and some nuts and seeds, are major components of the human cell membrane’s phospholipid bilayer and as such influence its structure and function.

Optimum levels can result in increased fluidity and permeability, potentially aiding cross-cell membrane transport and communication.

Omega 3s are also believed to affect enzyme activity that has a direct involvement in various neurotransmitter pathways.

Research evidence has identified that omega 3 EFAs reduce inflammation and increase serotonergic and dopaminergic activity whilst decreasing concentrations of noradrenalin.

These properties are thought to have a positive effect on depressive illness.

Deficiencies may reduce neurotransmitter signalling which plays an important role in the pathophysiology of psychiatric disorders.

In depressed patients where omega 3 deficiency exists a diet rich in omega 3 EFAs may exert positive benefits in treating this condition.

This has been confirmed by studies that have linked high fish consumption to low incidences of mental health disorders and this is seen to be a direct result of omega 3 intake.

Recommended dosage is 1 to 2g of omega 3s a day.

However for individuals with mental disorders up to 9g a day has been shown to be a safe dose.

A 150g portion of salmon will provide approximately 1.8g of omega 3 EFAs.



There are a variety of ways to tackle the symptoms of SAD but like many conditions, you may need to tailor your treatments to find therapeutic approaches that suit you personally. Finding the missing jigsaw pieces could be the answer to years of miserable winters.

Try these:

  • Exercise

Boring I know but exercise is often the key to recovery in many health conditions and SAD is no exception

Regular exercise really helps to improve mood and boost energy and is particularly helpful if you do it outside to make the most of the natural sunlight.

Studies suggest it elevates the feel-good hormones in the brain and packs a double punch if teamed up with a good dose of daylight.


  •  Re-Assess your diet

Instead of indulging in comfort carbs and sugary treats, change to foods like turkey, cottage cheese, bananas, chicken and avocado.

These are great sources of the amino-acid tryptophan which helps the brain produce happy hormones. 

Additionally, they are packed full of protein, which is vital for promoting new nerve growth and if eaten instead of succumbing to processed carbohydrates, may help to keep blood sugar levels balanced – reducing fatigue, irritability and sugar cravings.

Make sure you squeeze some oily fish, walnuts and flaxseeds into your diet too as these contain an abundance of omega 3 EFAs which are important components of structural nerve cell membranes in the brain.

EFAs can influence the health of the myelin sheath that surrounds the nerve fibres and aids the transmission and signals between neurons.

Deterioration of the myelin sheath affects nerve function and can lead to mental health problems.


  • Venture Out

Scientists have recently discovered that vitamin D is involved in the regeneration of myelin an important factor in maintaining brain health.

The body has a natural ability to repair myelin, but with age this becomes less effective.

Spend as much time as possible outside during winter to maximise your exposure to sunlight and stimulate the production of vitamin D in your body.

If howling winds and relentless rain are putting you off, now could be the time to pack your bags and head for a sunnier destination.


  • Invest in a ‘SAD’ lamp

Many SAD sufferers find light therapy lamps invaluable during the winter months.

Evidence suggests they help to reset the body’s own natural sleep/wake cycle which can be disrupted in those prone to SAD.

Hopefully with the help of a few carefully chosen nutrients and some lifestyle changes, winter will be a season to enjoy not hide from.





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