Vitamin F: function, foods, deficiency and supplements

23/11/20222 min read

While lesser known in the vitamin family, vitamin F is a key building block of membranes. Find out about this vitamin here, including foods and function.

Find out all about vitamin F, including what it does, how much you need, where to find it and who might need to supplement their diet

Written by Beth Gibbons on February 15, 2019 Reviewed by Amanda Hamilton on February 24, 2019

Overview

What is vitamin F and what does it do?

Vitamin F is actually a blend of fatty acids, the majority of which is linoleic acid or omega-6.¹ Omega-6 is an important source of energy, as well as playing a role in numerous tasks from brain function and immune response, to skin and hair health.² The body is unable to produce linoleic acid naturally, which means we need to get it from our diet.³ This makes it an essential fatty acid, like omega-3.

Function of vitamin F

What does vitamin F do in the body?

Linoleic acid is a key building block of membranes throughout the body,⁴ helping to move water in and out of cells. In the skin, it is converted to ceramide, a protective compound that allows cells to retain moisture.⁵ There’s also some evidence that the omega-6 fatty acid can help reduce the inflammation associated with autoimmune disorders such as psoriasis and rheumatoid arthritis.⁶

How much vitamin F do I need?

UK experts say linoleic acid should make up at least 1% of your daily calorie intake, while the European Food Safety Authority recommends an ‘adequate intake’ of 4% – the minimum needed for good health.⁷ Most of us already get enough omega-6, so you don’t need to worry about upping your intake. It’s actually omega-3 that’s thought to be more lacking in our diets, so most advice on getting enough EFAs tends to focus on redressing this imbalance.

Do children need vitamin F?

The World Health Organisation says very young children can get at least half their daily omega-6 requirements from breast milk⁸ – breast milk is naturally rich in linoleic acid⁹ – while infant formula is usually fortified with the nutrient.¹⁰ Over the age of two, children need the same amount of vitamin F as adults.¹¹

Vitamin F foods

Which foods are the best sources of vitamin F?

Good sources of vitamin F include:¹²

vegetable oils, such as rapeseed oil
seeds, such as flax, pumpkin and hemp
nuts, including walnuts and almonds
soybeans
tofu

Vitamin F deficiency

What are the symptoms of vitamin F deficiency?

A lack of omega-6 fatty acids can lead to dry skin and hair, and poor wound healing. In young children, low levels are also associated with slow growth and susceptibility to infection.¹³

What happens if I consume too much vitamin F?

A healthy, balanced diet should provide all the vitamin F your body needs. But there’s some concern that we’re consuming far too much omega-6 and not enough omega-3. It’s thought that too much omega-6 can stop the body using omega-3 properly, upping your risk of heart disease.¹⁴ A good ratio of omega-6 to omega-3 is around 4:1, but you don’t need to start eating a lot of omega-3s to try to balance out your diet.¹⁵ Scientists say reducing your intake of omega-6 – and in particular, vegetable oils – and eating two portions of fish a week, one of which should be oily fish, such as salmon or mackerel, is the best way to ensure you’re getting the right balance of both fatty acids.¹⁶ If you don’t like oily fish, or struggle to eat enough, omega-3 supplements or blended omega oils can be very helpful. Good plant-based sources of omega-3 include chia seeds, nuts and flaxseeds.

Vitamin F supplements

When should I take vitamin F supplements?

You don’t need to take a vitamin F or omega-6 supplement if your diet includes a wide range of healthy, nutritious foods.

Should children take a vitamin F supplement?

No – like adults, children can get the right amount through their diet.

Should women take a vitamin F supplement during pregnancy?

If you’re following a well-balanced diet, an omega-6 supplement during pregnancy is not necessary.

What are the potential benefits of vitamin F?

Linoleic acid has been shown to have a number of positive effects on cardiovascular health:

research by the Harvard School of Health in 2017 concluded that replacing saturated fats with polyunsaturated versions, rich in linoleic acid, can help lower the risk of heart disease¹⁷
a 1991 study published in the European Journal of Clinical Nutrition found adults who ate a diet rich in linoleic acid for three weeks reduced their LDL cholesterol levels by 18% after just two weeks¹⁸
after analysing data on 4,680 adults from multiple countries, Japanese researchers reported that people who ate more linoleic acid had lower blood pressure than those eating less omega-6¹⁹