Difference between Food Allergy and Food Intolerance

Both a food allergy and intolerance can make your body sensitive to a particular food or ingredient causing unwanted physical reactions whenever you eat the foodie culprit.

Only 2% of the adult population have a food allergy, where as 45% have a type of food intolerance.

Food allergy occurs when an antigen or trigger in the food reacts with specific immunoglobulin (also known as antibodies) in the immune system, as your body recognises the food as a foreign substance (allergen) when eating the food for the first time.

When you eat the offending food again, the antibodies attack the allergen, producing histamine and other chemical, setting off various types of symptoms.

Some foods are also naturally high in histamines. These include aged and fermented foods and alcohol (especially red wine), some people are sensitive to these types of foods.

‘Histamine poisoning’ can happen if you eat fish not kept at safe temperatures and has spoiled before you ate them. Those fish can build up high levels of histamines, which can make you sick.

Anaphylaxis is the most dangerous kind of an allergic reaction, involving the breathing and circulation, and causing faintness and shock, with a fall in blood pressure and in serious cases can lead to death (nut allergy, for example). Symptoms of food sensitivity include swelling of the lips, diarrhoea and vomiting. You may have eczema, a very runny nose or asthma.

Usually the reaction is acute and immediate, but it may be delayed, as in the case of coeliac disease (gluten being the allergen).

A food allergy can be tested by a patch test or blood test from your local doctors.

Food intolerance reactions are not caused by the immune system but is brought about by other mechanisms. For example, a milk intolerance (lactose intolerant) is due to a lack of a particular digestive enzyme, lactase.

Some active chemicals may be present in the food causing a reaction, such as caffeine, causing a racing heart and tremor. Some suffer from food additives provoked by hypersensitivity.

The timing of these symptoms vary, swelling tissues, vomiting and a runny nose appear within one hour. Rashes and diarrhoea may take longer, 2-24hours. Some disorders, headaches and irritability, may last for several days.

Long term problems relating to food include irritable bowel, hyperactivity disorder and migraine.

A food intolerance causes different reactions for different people so there is no definite test to find out your food intolerance. Monitor what you are eating and how it makes your body react and always seek professional advice from your local doctor.

In some cases, weeks or months of elimination of the intolerant food may well lead to reintroduction of the food without a reaction, as your body learns to build up a tolerance.

For further reading please see here there is a wealth of free food fact sheets on the Association of UK Dieticians website, all very useful and available here.


The Digestive System: The Oesophagus

human_digestive_systemIn my last digestive system post I mentioned the importance of chewing your food properly to help in the process of digestion: Read more here.

Chewing, physically and chemically breaks down your food. In Channel 4’s recent programme of #HowToLoseWeightWell one experiment looked into this and found the group that chewed their food more consumed less calories and felt fuller faster.

It also looked at how our saliva continues to break down food after it has left the mouth.


The Oesophagus

Once our food is swallowed it enters the oesophagus, also known as the gullet. This approx. 8 inches long muscular tube forces the food, now a rounded mass of food called a bolus, down towards the stomach using peristalsis. This is the process where the muscles in the wall of the tube massage the bolus by constricting and relaxing in waves pushing the contents on its way. It is a quick process taking 8-10 seconds, or less than 5 seconds using gravity if the body is in an upright position.

The oesophagus has two sphincter muscles at either end of the tube. The upper oesophageal sphincter (UES). The muscles of the UES are under conscious control, used when breathing, eating, burping, and vomiting. While keeping food and secretions from going down the windpipe.

The lower oesophageal sphincter (LES) is a bundle of muscles at the low end of the oesophagus, where it meets the stomach. When the LES is closed, it prevents acid and stomach contents from traveling backwards from the stomach. The LES muscles are not under voluntary control. An incompletely closed LES allows acidic stomach contents to back up (reflux) into the oesophagus. This acid reflux can cause heartburn.

An indication at this point that you have eaten something your body can’t deal with will be the muscles walls constricting and swelling, this can happen due to an allergic reaction. Another can be a burning sensation and warmth in the gullet immediately after swallowing, this can be felt in the effects of  alcohol, which is actually causing the gullet to become inflamed.

Find out about the stomach in the next post about the digestive system.

Lost Your Appetite?

We all experience at loss of appetite at some point, especially after being ill and having a stomach upset.

So how do we encourage our stomach and minds to want food again?

One thing not to do is miss any meals thinking it will increase your appetite for at least one meal in the day. The trick is to eat around six small meals a day to stimulate the appetite twice as much as three substantial meal or none at all.

These meals should be of small quantities and light on the stomach, for example mashed bananas, yoghurt or scrambled eggs. To ensure you are getting the nutrients you need have high-calorie, high-energy foods or have as a smoothie for easier consumption.

Along with these type of foods you may want to take a multivitamin supplement to wake up a dull appetite. A lack of appetite is also a symptom linked to Zinc deficiency, as it is essential for your body’s normal function and development. Zinc can be found in steak, pumpkin seeds, brazil nuts and egg yolk. Most Zinc is lost when food is processed so you may want to take a supplement as you may not feel like eating an oyster or an 8oz steak which both give you the 15g of Zinc as part of the Recommended Daily Allowance (RDA).

Fresh air and gentle exercise will help improve normal day to day functions, a stroll around your local park will do wonders to perk up your appetite.

Make sure you are drinking plenty of water, take sips throughout the day, if you drink one or more glasses in one go this will make you feel fuller, especially just before a meal.

Cook food that smells and looks good to awaken your senses and hopefully your appetite.

Make the most of your meal times by being in a relaxed environment, without any distractions and I advise not eating in the room you have been spending your days ill in as this might make your loss of appetite worse.

I know when I’m at home alone and have a lot to do, I often lose track of time and forget to eat altogether. The best way to avoid this from happening is to keep a clock nearby or set alarms on your phone to remind you to eat. Sometimes we have so much to think about eating isn’t our top priority but in order to have enough energy we need to eat.

So make sure you are fuelling yourself up to succeed, even if it is just for finishing the housework.


The Digestive System: Inside the Mouth

In my first post I mentioned listing foods as ‘safe’, ‘tolerable’ and ‘intolerable’ based on how your gut reacts to them and gave you a list of generally safe foods and avoidable foods to give you something to start adding meals around.

The type of foods you are eating may not be the only problem to your digestive system but there are ways we can prevent and reduce any inflammation and upset.

Our bodies work like a machine and when it works well everything is in perfect harmony; input, process, output. Together, a combination of nerves, hormones, bacteria, blood, and the organs of the digestive system completes the complex task of digesting the foods and liquids a person consumes each day.

So with that in mind, let’s see what ‘equipment’ (our organs) we have to work with.


The image above is a typical one you will find for the digestive system but it is worth remembering the effects on your digestion happen before you even start eating.

To aid digestion and reduce the risk of any upsets make sure you are mentally ready to eat. If you are stressed or unhappy it is best to give yourself some time to unwind before having a meal. When ready sit upright, dining chairs are ideal, as this does not constrict your stomach activity. Now you are ready to eat…

The Mouth

Your mouth is the first indicator whether a food is okay to eat, along with your sense of smell, take gone off milk for an example. If you like the smell and taste of the contents then your saliva glands will produce the enzyme ptyalin (also known as amylase), this is used to breakdown carbohydrates, converting starchy food, like bread, into maltose; a sugar which can be absorbed immediately.

It is thought that less than 5% of all starches consumed are digested within the mouth, before being swallowed as most of the digestive changes occur later on. This is because starch is a type of complex carbohydrate, which means that it’s made of long chains of sugars called polysaccharides. Foods high in starch, such as potatoes and some other tubers and root vegetables, are not as easily digested as simpler carbohydrates such as fruit, baked goods and pasta.

Therefore to help with this process it is important to chew your food as much as you can, it is recommended up to 32 times, if possible. Chewing for longer means your meal will last longer, making you eat smaller portions, one reason for this could be the time taken for your brain to signal that the stomach is full. This usually takes around 20 minutes.

When large particles of improperly chewed food enter your stomach, it may remain undigested when it enters your intestines. There, bacteria will begin to break it down, or in other words it will start to putrefy, potentially leading to gas and bloating, diarrhoea, constipation, abdominal pain, cramping and other digestive problems.

To reduce these problems, take smaller bites and swallow what you have already chewed before taking another bite. To reduce the symptoms of wind and bloating, try not to take down air when drinking or swallowing food.

Look out for more updates about processes throughout the digestive system coming soon.

My Diet through the Years


young-me-in-maccydI was a very fussy eater. I didn’t like different foods touching and often I would eat one thing on my plate to then move onto the rest rather than mix it all together. I would go days and sometimes weeks of just eating the same thing, I remember one time only wanting to eat sausages all week and nothing else and another time only wanting to eat dairy. Luckily I’m now over all these odd phases. I would definitely say my diet was unhealthy, as you can tell from the image above (I’m on the right) even if it was for my niece’s birthday.

Teenage Years

For many years I was a pescatarian, it made it easier for my Mum who did most of the cooking as my Dad was too but it was my decision and I felt good for having more fish and vegetables and cutting out meat. However, a lot of the go-to vegetarian freezer food has wheat involved. So I probably didn’t help myself by having toast or cereal in the morning, taking a packed lunch with a sandwich, crisps and most likely a cheese-string as they were popular back then and goodness knows whatever unhealthy snacks. I do remember going through a phase of giving away the unhealthy things to other class mates or trading my chocolate bar for an apple.


This is when my problems began… actually to be honest I’m sure they began a lot sooner. This is really where I started paying attention to what my body was telling me, not that I had much choice as I was continuously being ill. I knew I had to figure out what was triggering my discomfort after eating, I monitored my pains and found I felt particularly bloated after eating, especially at lunch. I used to have sandwiches, cheese or ham and yoghurt and fruit. I decided to cut out wheat and dairy and introduce things slowly. I quickly found out wheat was my main culprit.

I changed my morning toast for porridge and have rice cakes instead of bread for lunch. But I was still having pains. I took out oats, therefore porridge and was feeling better.

It wasn’t as simple as it sounds and had quite a few trips to the doctors and phone consultations before I was prescribed to have IBS tablets, because I had already cut out wheat from my diet I couldn’t have a blood test to see if I am coeliac and I don’t fancy a tube inside me for someone to tell me there’s no cure but to eat well. Although, in desperate times I did try a holistic allergy test involving changes in muscle strength when in close proximity to different allergens. Using this method it claimed I am allergic to gluten, wheat, strawberries and green beans, an unproven test but seemed to be quite accurate for me.

Now (25years old)

I am far from being healthy, I’m still catching every cold I come in contact with and sometimes my stomach will unexplainably upset or will feel uncomfortable after food and some days I just feel absolutely exhausted. So I have decided to really monitor what I am eating and would like to share my journey to help others and gain more knowledge and basically – get to grips with my gastro system and find a friend in food rather than seeing it as something that bothers me!

The first change was to swap sunflower oil for olive oil, which is a more stable fat and therefore healthier… look out for a post on cooking oils coming soon.

I try to make sure I have eggs at least once a day, avocado too, if possible for protein, vitamins and minerals – a whole lot of good stuff!

Using my ‘safe foods’ my foundation diet of these foods is as follows;

Breakfast -Two eggs and half an avocado (or whole depending on size)

Lunch – A range of organic greek yoghurt, goats cheese on rice cakes, nuts with half a cube of dark chocolate and fruit (banana, apple) and sometimes a carrot or two.

Evening Meal – Based around rice or potato (mostly jacket potato with skin on) with fish or chicken and vegetables.

I drink a lot of water, at least a pint or more before I set off for work and always have a glass next to me throughout the day.

In the morning and evening I tend to have peppermint tea or any herbal tea that has a mix of peppermint to aid digestion, plus keeps the breathe fresh after all the eggs and fish!

I have tried and should try harder to have sauerkraut on the side of every evening meal as it full of ‘good’ bacteria to help inhibit bad bacteria in the gut.

I have just started out on this new diet and will keep posting as I discover new things. I have already started, as mentioned in my last post, identifying my own ‘safe foods’ and intolerable foods.

Safe food: Cashew Nuts

Intolerable food: Peppers

… learning something new everyday!

Make a list of ‘safe foods’

Categorise your food into ‘safe’, ‘tolerable’ and ‘non-tolerable’.

You will want to start off with ingredients in your diet which are safe foods and work out which foods are best for you from there, everyone is different, so this helps to see what foods are best for you.

By making a list you can clearly see what your gut can tolerate and that’s when you can start to plan ahead your meals for each day.

Starting off with already known safe foods and introducing different things into your diet will give you a clear idea of what foods to avoid, hopefully making less ‘bad days’. If you do however have a ‘bad day’ go back to your list of safe foods, as this will be the foundation of your diet until you can introduce new foods again.

Foods that will be a good base to your diet will be the following:

  • Rice
  • Eggs (full of protein but intolerable for some)
  • Bananas
  • Avocado
  • Fish such as smoked salmon and mackerel
  • Peppermint Tea (I prefer this warm to cold as I find it hard to tolerate hot drinks)
  • Ginger
  • Turmeric
  • Sauerkraut
  • Potatoes with the skins on
  • Chicken
  • Yoghurt (organic greek yoghurt or probioctic, avoid if dairy intolerant)

Even some of the above can not be tolerated by some, so choose the ones that are kind to your own gut. These will give you a balanced, varied diet providing you with the vitamins and minerals which would have otherwise not been absorbed fully into the system when on a ‘bad day’. Supplements can be taken but always along with a healthy diet, in my own opinion supplements are aids to help you absorb more nutrients than you are able to in your diet but should never be replaced with any meals or food categories.

Certain things that are best to avoid to start with:

  • Vegetables and Fruit with skins on
  • Caffeine
  • Fatty Foods
  • Fizzy Drinks
  • Wheat and Gluten
  • Milk

The above are mostly ingredients that our stomachs find hard to digest, these tend to cause bloating and discomfort by taking the above out of your diet for a few weeks it gives your gut a chance to calm down and return to a norm.

If having a whole new diet change is a bit daunting to yourself and your gut, just make small changes, for example start replacing your morning coffee for a peppermint tea instead.

Good luck and if this post has helped at all let me know.

I will be going into more details on later posts about everything noted above.