This week I got to speak on BBC Radio Derby about tinned food. The presenter, Andy Twigge, was set a challenge to live off nothing but tinned food for a whole week! He almost did it, but caved when offered a Sunday roast! He experienced headaches, fatigue and excessive gas (from both ends!), plus his appetite decreased and just wasn’t fussed about eating (more tinned food anyway!).
The aired interview was shortened quite a bit so a few key points I mentioned were missing, so I thought I would write a blog post explaining in more detail why we shouldn’t live off tinned food!!
- The food in most tinned foods are highly processed. I’m talking about the meals, soups, beans etc. you find in cans which Andy was living off and which I’m sure many people consume on a weekly basis. Any form of processed food is low in nutrients, tend to be high in trans fats, sugar, salt and low in fibre. So they will give you very limited nutritional benefits causing your body to be deprived.
- Usually the foods contain a lot of salt. Salt preserves the food which helps it have such a long shelf life. One of the cans of soup Andy bought in to show me contained about 1.5g of salt in just half a can! Now, half a can isn’t going to keep you full for very long, so I’d be surprised if many people just have half and how many actually consume the whole thing! Giving them a whopping 3g of salt in just one sitting! I would recommend consuming no more than 3g of salt a day. Some recommendations go up to 6g a day, but from many of the genetic tests I have done with clients, if you don’t know your genetic ability to cope with salt, aim for 3g to be on the safe side! For those with the polymorphism (like me!!), consuming more than 3g a day (roughly 1500mg sodium, about 1/2 tsp of salt) increases their risk of high blood pressure by a whopping 230%!!! 1/2 a teaspoon really isn’t a lot even when eating whole foods, but when consuming processed foods, you will get more than that in one meal.
- The type of salt also isn’t good. Most of the tinned foods will use table salt which is just sodium chloride. Table salt often also includes anti-caking agents and added fluoride which are both toxic. We do need salt in our diet, but it should really be coming from an unprocessed source such as from our foods or sea salt. Sea salt doesn’t just contain sodium and chloride, it also contains other trace minerals such as magnesium (common deficiency in our society), potassium, calcium, phosphorus (needed for calcium uptake into bones), silicon and vanadium (helps with blood sugar control).
- Usually the foods contain high amounts of sugar. This is usually refined sugar or glucose syrup. Again it could be added to help preserve the food, or just to make it taste nicer and to be more addictive!
- The processing of the food requires high temperatures to help preserve it. This heating destroys many nutrients including water soluble vitamins such as vitamin C (needed for our immune system) and B vitamins (needed for energy production). If you’re consuming a lot of tinned food, you will begin to be depleted in these nutrients.
- The cans contain BPAs (bisphenol a) which is a chemical. Many people are aware of plastics and BPAs and therefore opt for BPA free water bottles, tupperware etc. However many are unaware it’s also in cans. BPA is a known hormone disruptor and can therefore lead to hormonal issues, man boobs (!) and has been linked to hormonal driven cancers.
- Foods high in fat or acidic foods leach BPAs even more. So if you were buying a tin of chopped tomatoes, which are acidic, there will be more BPAs than a tin of peas. Also, a tin which contains olive oil, will contain more BPAs than a tin with just water. With these foods, try to buy in glass jars or fresh.
I am not saying you have to avoid all tinned foods. However, I would recommend limiting them to essential items. I occasionally use tinned chickpeas, butter beans, lentils etc, but I would always opt for them in tetra paks or glass if possible. I ALWAYS buy tomatoes in glass rather than a tin. You can get tomato passata in glass in supermarkets and this can be used instead of a can of chopped tomatoes.
Remember, whole, natural foods are always best. If you can’t always get fresh, choose frozen over tinned foods e.g. frozen peas and sweetcorn instead of tinned. They will contain more nutrients and they don’t have the BPA’s. Try to always stay away from highly processed foods such as pre-made meatballs, chilli, soup etc. whether it’s in a can or not! And lets face it, fresh food always tastes better anyway!!