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7 common dietary reasons why you might be feeling tired

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There are usually a number of factors involved when an individual is constantly feeling tired including lack of sleep, stress, being inactive (or overtraining), and poor diet. When it comes to diet, a balanced varied diet is always advisable. However, here are 7 common dietary issues that can contribute to feeling tired.

Carbohydrate intake is too low

Often when trying to lose weight for example, people try to reduce carbs. However, often this can be too low. When carbohydrate intake is too low several things can happen. Firstly the stress hormone cortisol increases. There is also a lack of glucose (from carbohydrate) going to the brain, and glucose from carbohydrate is the brains preferred source. We also lose water and sodium from the body when eating a very low carb diet which can lead to mineral imbalances, lower blood pressure (hence why you might feel light headed) and lethargy. All of this can lead to tiredness, irritability and low mood.

You can reduce your carbohydrate intake by cutting out refined sugary carbs and reducing portion sizes, but you should still include healthy carbohydrate foods in the diet. Healthy carbohydrate choices include fruits, vegetables, whole grains and pulses. Try to limit processed refined carbohydrates such as foods with added sugars and white bread which offer little or no nutritional goodness.

Not getting enough iron

Iron deficiency is common particularly in women. It is an essential mineral and one of its many roles is to make red blood cells which carry oxygen around the body. Too little iron in the body can lead to iron deficiency anemia which can make us feel tired and lethargic. Although important for men too, women need to consume more iron compared with men which is mainly due to having periods.

Food sources of iron include meat, beans, dried fruit, nuts, dark green leafy vegetables such as kale, wholegrain foods and liver. Vitamin C can help absorb plant iron better, so try eating iron rich foods with vitamin C containing foods such as tomatoes or citrus fruits. Small quantities of good quality lean red meat a couple of times per week will help increase iron levels.

Not enough vitamin D

As well as contributing to healthy bones, vitamin D is also needed for muscle function and plays an important role in keeping the immune system healthy. Lack of vitamin D in the diet has been linked to fatigue as well as poorer immunity which can also lead to tiredness. The main source of vitamin D is from the action of sunlight on the skin. Food sources include oily fish and eggs and some foods are also fortified with vitamin D such as spreads and some breakfast cereals.

Not enough water

Water is needed for a number of things in the body including transporting and eliminating toxins, and the absorption of nutrients throughout body and brain. Being dehydrated can therefore effect energy levels as well as our ability to think clearly and concentrate.

Too much caffeine

With it being a stimulant, small amounts of caffeine, in the form of coffee for example can be a good way of increasing mental alertness and gives us a bit of a ‘pick me up’. However as coffee stimulates the adrenal glands (leading to increase in the ‘fight or flight’ stress hormones such as adrenaline and cortisol), if it is consumed in excess eventually the natural chemical balance in the body can become out of whack. This can lead to feelings of fatigue as well as low moods and food cravings.

Eating too many processed foods

Soft drinks, sugary snacks (such as snack bars), packaged ready meals etc. all contain high amounts of added sugars. Too much added sugar in the diet can cause a cascade of chemical reactions promoting chronic inflammation which leads to low moods and tiredness (as well as increased fat storage).

Training regularly but your nutrition is not optimal

We need to recover properly after training to replenish energy levels and for building and repairing muscle. Not eating optimally means that we are less likely to recover before the next training session leading to greater muscle soreness, fatigue and increased chance of illness. Make sure your carbohydrate and protein intake is sufficient throughout the day as well as getting a good intake of healthy fats (e.g. from oily fish, nuts, olive oil) and lots of fruits and vegetables for a good intake of nutrients.


*disclaimer: this article is based on my own professional opinion and is not meant as a way of diagnosing underlying conditions. If you have been feeling tired or lethargic on an on-going basis it may be advisable to see your GP.   

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