Fat-soluble Vitamins

Vitamins are required for different essential functions within the body. When we talk about vitamins there are two categories that we can divide them into: 

  • fat-soluble vitamins 
  • water-soluble vitamins 

When we eat fat soluble vitamins, we need a small amount of fat with them to allow them to be absorbed and utilised by our body. Fat-soluble vitamins include:  

  • Vitamin A 
  • Vitamin D 
  • Vitamin E 
  • Vitamin K 

We can store these vitamins in our liver and adipose (fat) tissue and they are not easily excreted, which means in excessive amounts they can have a toxic effect on the body. Deficiencies usually only occur in cases where there is malabsorption of fat (and therefore fat-soluble vitamins).  

Vitamin A  

Vitamin A (retinol) is only found in animal sources such as: 

  • Eggs 
  • Oily fish 
  • Dairy products 
  • Liver 

We can also make vitamin A through good, plant sources of beta-carotene, which our body then converts into vitamin A. Sources of beta-carotene include dark-green, yellow and red vegetables and fruits, such as: 

  • Spinach 
  • Carrots 
  • Sweet potatoes 
  • Peppers 
  • Mango 
  • Apricots  

What Does Vitamin A Do?  

It helps with our vision in dim light; helps to maintain healthy skin and a lining on parts of the body, especially those that secret mucus like the nose. Vitamin A also helps to make sure that the immune system is working properly. 

Do I Need to Supplement?  

No, you should be able to get all the vitamin A that you need through your diet, as it is a fat-soluble vitamin. Any vitamin A that is not needed is stored for times when it may be required.  

Large amounts of vitamin A can also harm your baby if pregnant, which means that liver should not be consumed, and supplements containing vitamin A avoided, including fish liver oils. 

Sweet potato dauphinois

Vitamin D 

In the UK between March to September, most of us at this time of year, can synthesise vitamin D from the sunshine! This is possible from around late March/early April until the end of September.     

The amount of time required to synthesise enough vitamin D is not known, as there are a few variables which play a role in the synthesis. It is roughly a short period of time for lower legs, forearms and hands; however, it is important to ensure that you do not burn and if out for long periods of time sun protection should be used.   

Synthesis can be impacted by:  

  • Skin colour (dark skin takes longer to synthesise the same amount of vitamin D as someone with light skin)  
  • How much skin is uncovered  

You also cannot synthesise vitamin D through a window, as the UV rays which are needed cannot go through glass.   

There are some groups which should consider talking to their health care professional and supplementing all year round (10mcg (400IU) per day), these include:  

  • Babies from birth-1 year should have a daily supplement of 8.5-10mcg per day if breastfed. Those having over 500ml of formula milk a day should not supplement as the formula is fortified with vitamin D   
  • All children aged 1-4 years should be given a daily supplement of 10mcg  
  • Those who aren’t often exposed to sunlight should also consider a 10mcg supplement  

Sadly, in the winter between September to late March in the UK, we are no longer synthesise vitamin D from sunshine. So, what can we do? Well it is recommended that between the months of September to late March/early April we supplement for our vitamin D.  

How Much Do We Need to Take?   

It is advised that adults and children over the age of 1 supplement with 10mcg (400IU) a day. Unless recommended by a doctor or a dietician about a higher dose, you do not need to exceed this recommendation.   

You can also get a small amount of Vitamin D from food sources, these include  

  • Oily fish  
  • Egg yolks  
  • Some mushrooms if they have been exposed to UV rays  
  • Fortified foods  

What Does Vitamin D Do?   

Vitamin D is a fat-soluble vitamin, which means we store it in our fat tissue. It is involved in keeping our bones, teeth and muscles healthy; absorbing calcium and phosphate; as well as being linked to helping our immune system; reducing inflammation; and potentially even playing a role with heart conditions, diabetes and asthma.  

Vitamin E 

Vitamin E is mainly found in plant sources such: 

  • Olive oil 
  • Corn oil 
  • Nuts and seeds (including sunflower seeds and almonds) 

You can also find small amounts in meat, poultry and dairy.  

What Does Vitamin E Do?  

It is well known for being an antioxidant, helping to reduce free radicals in the body. It also helps to maintain healthy skin, hair and eyes; and helps with keeping the immune system healthy and strong. 

Do I Need to Supplement?  

As it is a fat-soluble vitamin, any excess amount of vitamin E that you consume will be stored for when it’s needed. So really you do not need to supplement this as you can get it from foods you eat.   

Crunchy chai granola

Vitamin K  

Vitamin K can be found in a wide variety of vegetables including: 

  • Kale 
  • Spinach 
  • Cabbage 
  • Cauliflower 
  • Broccoli 
  • Peas 
  • Cereals 

One type of vitamin K can also be synthesised in our intestines.  

What Does Vitamin K Do?  

Vitamin K is known for helping with the normal clotting of our blood and a deficiency in vitamin K can lead to bruising and excessive bleeding.  

Do I Need to Supplement it?  

Being deficient in vitamin K is rare unless you are unable to absorb and utilise vitamins. Most of us should be able to get the amount we need through a varied diet. It is a fat-soluble vitamin, so any that you don’t need is stored for future requirements. Newborn babies at birth are giving a vitamin K supplement to prevent deficiency. 


Roasted vegetables and chai spiced lentils

Other blogs you might be interested in:

Daisy, MSc PGDip ANutr, is a Registered Associate Nutritionist with a Master's Degree in Public Health Nutrition, and a Post Graduate Diploma in Eating Disorders and Clinical Nutrition, both of which are Association for Nutrition (AFN) accredited. She, also, has a BSc degree in Psychology and Cognitive Neuroscience; and has completed an AFN accredited Diet Specialist Nutrition course.

Daisy has worked for an NHS funded project, the Diabetes Prevention Programme; and shadowed a nutritionist in Harley Street. 

About Lucy Bee Limited

Any information provided by us is not intended to diagnose, treat, cure or prevent disease. We always recommend referring your health queries to a qualified medical practitioner.

Lucy Bee is a lifestyle brand selling food, skincare and soap products all completely free from palm oil and with minimal use of plastic. Lucy Bee is concerned with Fair Trade, organic, ethical and sustainable living, recycling and empowering people to make informed choices and select quality, natural products for their food and their skin.

Back to blog

Leave a comment

Please note, comments need to be approved before they are published.