It feels like recently it’s impossible to escape negative headlines or posts on social media around ingredients in our foods, or certain foods that we should be avoiding. Seed oils are an ingredient that have been demonised more and more, and I’m often asked about whether we should be worried about offering seed oils, or foods that include them to our children.
I’ve recently written about the topic of food additives and whether these should be avoided, but in this blog I want to talk specifically about seed oils in our kids’ foods. I’ve also written a detailed post about processed foods in our kids’ diets which has plenty of practical details about how to manage these foods when it comes to our children.
What ARE seed oils?
Seed oils is the name given to oils extracted from plants. They are also known as vegetable oils. Some of the seed oils we commonly use are:
- Sunflower oil
- Rapeseed oil (known as canola oil in the US)
- Soybean oil
- Grapeseed oil
- Safflower oil
Seed oils are popular choices of cooking oil as they are relatively neutral in flavour and also quite affordable and easily accessible.
What are the concerns around seed oils?
The concern around seed oils is that they contain high levels of omega-6 fatty acids. In particular, the concern is around linoleic acid, which is a type of omega-6 fatty acid, and converts into arachidonic acid in the body. Arachidonic acid is a compound that is a building block for certain processes which trigger inflammation in the body.
You can therefore understand the argument against seed oils – that if they contain high amounts of linoleic acid – and this converts into arachidonic acid – then eating Omega 6 must trigger inflammation in our bodies (see more on inflammation below).
However, the current evidence we have on humans (the only studies that are really relevant to our health!!) doesn’t actually back this up. Most recent studies have actually shown that diets high in linoleic acid don’t appear to result in higher levels of inflammation at all. Additionally, other research into those consuming a high linoleic acid diets have even shown a reduced risk of cardiovascular disease and of developing type 2 diabetes. Chronic inflammation is a factor in the development of both of these diseases, so it’s notable that a high intake of linoleic acid has actually been associated with less disease.
This suggests that the theory that high levels of the Omega-6 linoleic acid increase inflammation in the body, doesn’t seem to be accurate in the human population. The majority of the research that has sparked concern around seed oils has been carried out in rodents, which aren’t relevant to the human population, particularly when we have evidence in humans to show that seed oils are not harmful to human health.
It’s also important to remember that ‘inflammation’ can sound negative – and whilst it is a process which is linked to many different diseases, inflammation is also a necessary part of how our bodies deal with injuries and illness. Inflammation is harmful when it happens in excess and is chronic – as happens in the development of cardiovascular disease or type 2 diabetes, for example.
For a really detailed breakdown of the research into seed oils and the research, check out this article.
What about the way that seed oils are processed?
Another concern surrounding seed oils is that they are heavily processed and therefore contain high amounts of harmful chemicals or trans fats. The processing of seed oils involves using heat, which can lead to the creation of trans fats. Trans fats are a type of fat that can increase cholesterol, which is linked with poor health outcomes. In the UK, the government has encouraged manufacturers to remove trans fats from their products and levels are generally low in our foods. Trans fats can be found in some meat and dairy foods, albeit in small amounts.
Hydrogenated vegetable oil – which is an oil made from various types of vegetables using a processing method called hydrogenation – does contain higher amounts of trans fats. Hydrogenated vegetable oil can be used in some processed foods, as it is used to increase shelf life.
However, according to the NHS, “most supermarkets in the UK have removed partially hydrogenated vegetable oils from their own brand products.”
Seed oils in the UK are regulated to ensure they don’t contain trans fats. They also undergo checks to remove other harmful chemicals – such as hexane. Only trace amounts of any chemicals involved in processing may remain in the final product.
What about the erucic acid content in seed oils?
Another ingredient that has caused some concern, particularly on social media, is erucic acid. Erucic acid is a monounsaturated fatty acid that has been shown in some old studies to have harmful cardiac effects on rats. Erucic acid mainly enters the food chain through vegetable oils, including rapeseed oil. However, processed versions of rapeseed that are used in our food systems contain significantly lower amounts of erucic acid – only making up around 0.5% of total fatty acids.
There has been some concern that children may be consuming too large amounts relative to their body weight. Reports suggest that the foods that contribute the highest proportion of erucic acid in the diets of 1-3 year olds are pastries and cakes whilst infant formula contributes to erucic acid intake in infants. However, there are strict regulations about the amount of erucic acid that can be present in infant formulas, which mean that food grade rapeseed oil used in infant formula cannot exceed more than 0.4% of the total fatty acid content in the rapeseed oil. When it comes to pastries, cakes and other processed foods that may contain higher levels of erucic acid, it’s important to note that these are foods that our little ones should ideally be avoiding or consuming in moderation anyway.
It’s also important to note that currently, the potentially harmful effects of erucic acid that have been studied in animals, have not been seen in humans. More research is always needed, but there shouldn’t be cause for concern based on current evidence and practices and regulations regarding erucic acid in our food chain.
Should we avoid foods with seed oils in for our children?
The headlines and claims that you may read about the harmful effects of seed oils, don’t appear to be backed up by research. A lot of research has been carried out on the consumption of seed oils, or diets that contain high levels of seed oils and the ingredients they contain. The consensus of the current research is that seed oils are not harmful to health.
There are also nutritional benefits that seed oils offer. Most vegetable oils contain omega-3 fatty acids, as well as omega-6 fatty acids, both of which offer nutritional benefits. Omega-3 fatty acids are a type of polyunsaturated fats which have been linked to many positive health outcomes, including improved heart health, mental health and they also play an important role in brain development. Including a variety of different fats in our children’s diets is important, and cooking with seed oils can be an affordable and accessible way to include some beneficial fats in their meals.
Something I ALWAYS talk about when it comes to what foods our kids ‘should’ and ‘shouldn’t’ have is VARIETY. As much as possible, try to include a wide variety of different fats in your little one’s diet – vary up the oils you use, include foods like avocado, nuts, seeds and oily fish if your little one has fish.
It is ideal to be aiming for a balanced diet rich in whole, unprocessed foods with plenty of fruits, vegetables, wholegrains and legumes. However, this doesn’t mean that there isn’t room for other foods in the diet and that consuming these foods occasionally is going to cause your children harm. Fearing foods or being overly restrictive around foods can cause unnecessary anxiety for both you and your children.
If you are looking to reduce your family’s intake of seed oils, here are some things you can do:
- Vary the types of oils and fats you use – for example, include olive oil and add fats such as avocados, oily fish, nuts and seeds
- Choose quality oils if you can and it is accessible to you
- Check labels on back of packaging for ingredients and choose products without seed oils where appropriate
- Reduce your intake of processed foods wherever possible
Take home message
- Seed oils are an affordable and accessible cooking oil which offer omega-3 and omega-6 fatty acids, which contribute to heart health and brain development
- The current research around seed oils doesn’t back up claims that they lead to increased inflammation in the body
- Regulations in the UK mean that trans fats and other chemicals that may be present during processing are removed and do not remain in significant amounts after processing
- Seed oils can be used in some processed and ultra-processed foods. We should aim to limit these foods in our diet anyways, wherever possible. Including some processed and ultra-processed foods in our diet is not likely to be harmful when consumed in the context of a balanced and varied diet, and it’s unrealistic for most people to totally avoid including some of these foods in their diet.