Defence chemicals in vegetables, nuts and seeds. Whats the story?

Dr Ben Stride

I don’t know about you, but deciding what you can and can’t eat these days seems to be a total minefield. The amount of self professed tiktok and Youtube experts seem to be rising day by day and for every one “expert” that recommends one thing, another recommends the total opposite. So how can we make sense of all the noise and make good decisions?

The topic on the table for now is the increasing numbers of influencers who are proponents of the carnivore diet in order to avoid the so called defence chemicals. Individuals like Bear Grylls who once a defacto vegan, now a believer in avoiding vegetables, seeds and nuts due to concern for defence chemicals, the same man who televised himself on multiple occasions drinking his own piss. He is not alone in the belief that a highly restrictive diet including primarily meat and animal products, apparently like our ancestors, is the only way to live a long and healthy life. These are the ancestors who lived only a fraction of the life expectancy we have today. Whilst I disagree with the overall conclusion, I understand why people may want to avoid eating chemicals that plants create within themselves to deter tiny tiny, often imperceptibaly small animals from consuming them. I can also understand that when people suffering with autoimmune or gastroenterological issues take drastic dietary action, they improve their symtpoms and want to tell the world. However this is likely due to the elimination of the one causative allergen or irritant due to the severity of the dietary restriction and their self made pulpit fails to take into account the complexities of people and illness.

My main issue with the advertisement of this diet as the beacon of good health is that it fails to take into account the balance and the fact that something that works for the individual shouldn’t be advertised as the answer for a whole population. No doubt part of the youtubers’ stance serves to push their own products, but often it isn’t so easy to not be swayed by their extreme views.

There is some evidence that certain nuts, seeds, and vegetables contain natural defense chemicals that may be harmful in large quantities. However, it's important to note that the levels of these chemicals found in food are generally safe for consumption and that the benefits of eating a diet rich in nuts, seeds, and vegetables outweigh any potential risks.

For example, some nuts and seeds contain phytic acid, which can bind to minerals such as iron and zinc, making them less available to the body. However, the levels of phytic acid in most nuts and seeds are relatively low and can be reduced by soaking or roasting.

Similarly, some vegetables contain compounds called goitrogens, which can interfere with thyroid function in large amounts. However, cooking these vegetables can reduce the levels of goitrogens, and the benefits of eating a diet rich in vegetables generally outweigh any potential risks.

It's also important to remember that different people may have different sensitivities to certain foods. Making a food diary and monitoring symptoms is vital and can really help doctors narrow down the problem. The main lesson here though is that moderation is often the best approach. Anything in excess could put you at risk of some sort of illness and there will likely be a paper somewhere that suggests problems with one ingredient or another. If you have concerns about the safety of certain foods, it's always a good idea to speak with a healthcare professional or a registered dietitian.