Eliminate your hidden food allergies

The most common reason for weight gain caused by fluid retention is allergy. The word ‘allergy’ simply means an intolerance that cause a reaction in the immune system.

Your body is like a tube. The digestive tract, which has a surface area the size of a small football field, is the gateway between the outside world and your body. It’s guarded ferociously by your immune system. If a substance that isn’t on the guest list, so to speak, tries to gatecrash and get through your digestive tract and into the bloodstream, your immune system goes haywire.

The reason why food intolerance can lead to weight gain, and difficulty losing it despite going on reduced-calorie diets, is complex but is starting to be unraveled. The most common kind of food intolerance leads to the production of IgG antibodies, which activate an immune reaction when you eat an offending food. This, in tern, increases inflammation in the body, raising certain known markers for inflammation such as TNF-a and C-reactive protein (CRP). Increased inflammation also increases water retention and bloating, as well as other classic signs of food intolerance, including aching joints, headaches, blocked nose, irritable bowel syndrome and skin problems. However, these systems are often delayed by 24 to 48 hours, so it isn’t easy to know what you react to just by observing how you feel after eating a particular food. Nor is it easy to work out what you’re intolerant to just by observing how you feel by the short-term elimination of the food, because some people get withdrawal symptoms when they eliminate certain foods. To make matters worse, some potential offending foods, especially wheat and milk, have an immediate pay-off by producing opioid-like chemicals called gluteomorphins and caseomorphines that make you feel good. So, if anything, you are naturally drawn to these foods. The same is true with sugar, which, in the short term, promotes energy, but actually encourages inflammation and weight gain in the long term.

The more foods you eat that provoke IgG antibody reaction (tested in a simple allergy test) the worse it is for your health and your weight. Your immune system should not produce large amounts of IgG antibodies and, if it does, you are likely to suffer from some degree of general malaise and symptoms that just don’t seem to shift, as well as resistant weight loss.

For example, a recent study found that obese children had much higher IgG antibody levels than normal-weight children. “Anti-food IgG antibodies are tightly associated with low grade systematic inflammation and with the thickness of carotid arteries’, the study authors report. The researchers conclude that having IgG antibody reactions may be involved in the development of both obesity and atherosclerosis, and that a diet based on eliminating IgG-positive foods might be the way forward. Inflammation also affects the gut, potentially making the gut wall more leaky or permeable, which, in turn, may increase food intolerances.

The more often you are reacting allergically, the more more resistant you become to insulin. This is because the body releases masses of immune messengers called cytokines to deal with the allergy, and cytokines make you less responsive to insulin. Also, repeated allergic reactions mean that more garbage ends up in your bloodstream as your immune cells fight off the invaders.

As antibodies, cytokines and other immune cells move in to deal with allergic in invaders, they make a lot of mess that has to be cleaned up by your liver, your body’s detoxifying organ. Eventually, the liver’s detox capacity gets overloaded. When this happens, your body dumps the toxins in the least harmful place: your fat cells. The more intoxicated your fat cells become, the more weight you gain and the harder it becomes to shift those extra pounds. This is why people with allergies find it harder and harder to lose weight. Also, this continual process of overintoxication can turn a mild allergy into something severe. Many people don’t find out about their allergies until it’s really obvious.

Discover whether you’re allergic

Allergies can be responsible for many symptoms, especially digestive problems, from bloating to constipation, and diarrhea to abdominal cramps. These are almost always accompanied by mental and physical symptoms, such as mood changes, chronic tiredness, depression, increased appetite, sleepiness after meals, inability to concentrate and a host of minor ailments, from itches and rashes to asthma and sinus problems. Check yourself out with the questionnaire below.

Your instant allergy check

  1. Can you gain weight in hours?
  2. Do you get bloated after eating?
  3. Do you suffer from diarrhea or constipation?
  4. Do you suffer from abdominal pain?
  5. Do you sometimes get really sleepy after eating?
  6. Do you suffer from hay fever?
  7. Do you suffer from rashes, itches, asthma or shortness of breath?
  8. Do you suffer from water retention?
  9. Do you suffer from headaches?
  10. Do you suffer from other aches and pains, from time to time, possibly after certain foods?
  11. Do you get better on holidays abroad, when your diet is completely different?

If you have answered “yes” to any of these questions, there’s a real possibility that you have an allergy. If you answered ‘yes’ to four or more, it’s pretty much guarenteed.

Top Tip

Do you get bloated after eating and have to undo a button or two? If so, it is very likely you are eating something you are allergic to.

Pinpointing the allergen

It may seem odd, but more often that not the foods a person is allergic to are those they really crave. If you’re craving and eating something frequently, as though you’re mildly addicted, there is a chance you’re allergic to that food. Through my work with a number of allergic and overweight clients, it became clear to me that they were bingeing only on certain food groups. When they were instructed to eat as much as they liked of anything except the suspected allergen (the food provoking an allergic reaction), they often ceased to binge. And, when they avoided the allergen completely, they often lost 1.3 – 1.8kg (3-4lb) and occasionally as much as 3.2kg (7lb) almost overnight.

This sort of short-term weight loss can only be the result of excess fluid retention, and nothing to do with fat. You can’t burn 450g (1lb) of fat in 24 hours, even if you are starving – and much less 3.2kg (7lb)!

One of the physical symptoms of an allergic reaction can be a sudden fluctuation in blood sugar level that, in turn, affect appetite. So could allergic reactions trigger bingeing? In honesty, nobody has a definite answer to this question, but my observations of a number of clients certainly show that sometimes allergies do play a role in yours.

There are two ways to find out what you are allergic to. The first we could call ‘educated trial and error’. You need to avoid suspect foods for 14 days and note what happens by taking the pulse test, explained below.

The Pulse Test

Most people are free of symptoms within 14 days of avoiding an allergy-provoking food. And most will react on reintroducing the food within 48 hours, although some may have a reaction delayed by up to 10 days. Delayed reactions are much harder to test. For some people, symptoms improve considerably when they leave out the offending foods. For others, noticeable changes are slight.

One simple way to help identify possible suspects is the pulse test. The pulse test demands that you avoid all suspect foods for 14 days, then reintroduce them one by one, with a 48-hour gap between each item to be tested. Take your resting pulse, sitting down, before you eat the food, then take it again after 10 minutes, 30 minutes and 60 minutes. Write all this down on a chart. If you marked increase in pulse rate more than 10 points, or have any symptoms of ill health within 24 hours, including immediate weight gain, bloating, fatigue, headaches or joint aches, for example, avoid the food and wait 24 hours before testing the next food.

Although day-to-day changes in symptoms are hard to pin down to specific causes, avoidance of suspect foods for 14 days often lessens symptoms, which then increase significantly on reintroduction. So you’ll be able to pinpoint which foods or drinks make you worse. It is very important to observe symptoms accurately, because you may have preconceived ideas about what you do or don’t react to, perhaps because of what somebody told you, or because you dread being allergic to certain foods that you’re addicted to.

IgG allergy testing – the gold standard

Because the body sometimes delays its allergic reaction to a food, avoidance/reintroduction tests don’t always pick the allergy up. This happens because you may not suspect the food, and so not test it. Or you may suspect only one food, yet be allergic to a range of them, so you’ll continue to have a background of reactions and may thus have difficulty losing weight.

The best and truly accurate way to find out what you are allergic to is to have what’s called a Quantitative IgG ELISA test. This is the gold standard of allergy testing. “Quantitative’ means the test shows not only whether you are allergic, but also how strong your allergic reaction is. Many of us live quite healthily with minor allergies. But stronger allergies can create all sorts of problems, including weight gain. “ELISA” is the technology used. You don’t need to know all the details, but, trust me, it’s the most accurate system. If it’s done properly it is at least 93 per cent reproducible. It’s used by almost all the best allergy laboratories in the world.

To convey why it’s so good, I need to explain a bit about the human immune system.

Your immune system can produce tailor-made weapons that latch onto specific substances to help escort them out of your body. They are like bouncers on the lookout for troublemakers. The bouncers are called immunoglobins, or Ig for short. There are different types. The real heavies are called IgE, although most allergies involve IgG reactions. IgE reactions tend to be more immediate and severe. However, most ‘hidden’ allergies that may be insidiously causing weight gain are IgG-based. In an ideal world you test for both, but I normally start by testing a person for IgG sensitivity to food. If you’d like to find out more about the science behind IgG-based food allergies and intolerances go to

All that’s needed for testing is a pinprick of blood, which is absorbed into a tiny tube and sent to a laboratory. The lab then sends back an accurate readout of exactly what you are allergic to. Your body doesn’t lie. You either have IgG bouncers tagged for wheat (for example) or you don’t. Your diluted blood is introduced to a panel of liquid food ‘testers’ and, if you’ve got IgG for that food, a reactions takes place.

The good news about IgG-based allergies is that if you avoid the offending food strictly for three to six months, the body forgets that it is allergic to it. The reason is that there will no longer be any IgG antibodies in your system to that food. This doesn’t hold for IgE-based reactions, however.

To give you an example, I have an IgE allergy to milk. I react within 15 minutes. Even if I avoid diary products for a year, I still react if I consume some. I used to have an IgG to wheat. I avoided it for three months and now I no longer react. In my case, weight gain wasn’t the problem, it was migraine headaches. I had them every other week from the ages of 6 to 20, until I discovered that wheat and milk were triggering them.

Fenton R, like myself, had regular headaches, sinusitis and fatigue and had been plagued by acid indigestion for 20 years. He was also gaining weight year on year. Doctors were unable to help him, suggesting he drank too much fizzy pop and should exercise more. And indigestion tablets helped for only 20 minutes before the problem returned with redoubled force.

He decided to have a food intolerance test. The results came back showing he was intolerant of eggs, cow’s milk, yeast and wheat. He took all the rogue foods out of his diet, for example by switching to soya milk, , and within two days the indigestion began to ease. Now it has gone completely, along with all the other health problems that had dogged him – including an excess 12.7kg (2st.) in weight.

“It feels as though a shroud has been lifted from me. Not only have I lost the weight, but also have 100 per cent more energy. It used to be an effort to go up the stairs. I used to get headaches most days, and they have gone. I used to get sinus twinges almost every day, and that has cleared up. I used to sweat a lot, and thought I was just a sweaty person. But now I can walk and run and just don’t sweat. My skin used to be cold all the time but now it’s nice and warm. I feel more relaxed as well. It had got to the stage where I couldn’t even think clearly, but now I can do so again.”

The usual suspects

The most common foods or food groups that people are allergic or intolerant to are shown below, in order. Of all these foods, by far the most common allergy-provoking substances are dairy products, followed by yeast, eggs and wheat. This doesn’t necessarily means that these foods are bad for you, it just depends on whether or not you are allergic or intolerant to them.

The most common food allergies are:

  • cow’s milk
  • yeast
  • eggs
  • gliadin grains such as wheat (also rye and barley)
  • nuts
  • beans
  • white fish
  • shellfish

Cow’s milk

The most common food allergy is to cow’s milk. It’s present in most cheeses, cream, yogurt and butter and is hidden in all kinds of food; sometimes it is called ‘casein’, which is milk protein.

Logically, its status as an allergen isn’t suprising, since it is a highly specific food, containing all kinds of hormones designed for the first few months of a calf’s life. It’s also a relatively recent addition to the human diet. Our ancestors, after all, weren’t milking buffaloes. Approximately 75 per cent of people (25 per cent of Caucasion origin and 80 per cent of Asian, Native American or African origin) stop producing lactase, the enzyme that’s needed to digest milk sugar, once they have been weaned. Is nature trying to tell us something? However, it’s not the lactose – the sugar in milk – that causes the allergic reaction. It’s the protein.

If you react to cow’s milk, it doesn’t necessarily mean you will react to goat’s milk or sheep’s milk. However, many people do. It’s often best to eliminate all dairy food for the first three months, then try goat’s milk or cheese or yogurt.

As dairy is the most common allergen, it is used very little in the recipes in this book. If you do have difficulty tolerating it, you may find that you are all right with sheep’s- or goat’s-milk products. There are easier to digest though they have a distinctive, tangy flavour, much stronger than cow’s milk. However, if you’ve had an allergy test and it’s confirmed that you’re allergic to all dairy, avoid all of it, including yogurt and butter. In most cases, if you strictly avoid your allergy-provoking foods for three months, you body can ‘unlearn’ the allergy. So it doesn’t have to be a life sentence.

There are many alternatives to dairy now, including soya and quinoa ‘milks’. Try them out and find one you like.


After milk, yeast is the second most common culprit in allergies. Some people think they are allergic to wheat because they feel worse after eating bread. If you’ve noticed this – perhaps feeling sluggish, tired or blocked up – but feel fine after pasta, you may not be allergic to wheat, but to the yeast in the bread.Yeast is not only in bread as baker’s yeast but it’s also in beer and, to a lesser extent, wine. Beer and lager are fermented with brewer’s yeast. If you’ve noticed that you feel worse after beer or wine than after spirits – the ‘cleanest’ being vodka – then you may be yeast-sensitive. If you have been allergy-tested, you’ll know whether you are allergic to brewer’s or baker’s yeast. Most people who are allergic to yeast at all are allergic to both. Wines are yeast-fermented. Champagne has very little yeast. However, the only guarenteed yeast-free alcoholic drinks are pure spirits. Since you won’t be drinking much alcohol, it’s best to stick to spirits for the first three months so that your body has a chance to unlearn the allergy.

If you’re allergic to yeast, you’ve also got to be on the lookout for hidden yeast in stock cubes and processed foods. As the Holford Diet features wholefoods and fresh ingredients, and avoids yeasted breads, this should be far less of a problem for you. I also recommend using yeast-free vegetable stock cubes by Marigold.

A word about alcohol: as well as causing allergies in some, alcohol irritates the digestive tract, making it more permeable to undigested food proteins. This increases your chances of developing an allergic reaction to anything, and it’s why some people feel worse when they eat foods they are allergic to and drink alcohol at the same time. For example, you might be mildly allergic to wheat and milk and feel fine after either. But when you have both, plus alcohol, you don’t feel great.


This is the grain that more people react to than any other. It contains gluten, a sticky protein also found in rye and barley and oats. Gluten sensitivity occurs in about one in a hundred people, but it is medically diagnosed in fewer that one in a thousand. However, there is something in gluten, called gliadin, which some people react to specifically. The only way to know for sure exactly what you are allergic or intolerant to is to have a food intolerance test. If you have had an allergy test you’ll know whether you are sensitive to gluten, gliadin or wheat.

If you are gluten-sensitive, then you cannot eat wheat, rye, barley, or oats. Excellent alternatives are rice, quinoa, buckwheat, millet and corn (although some gluten-sensitive people do react to corn). Quinoa and millet cook in much the same way as couscous. From the GL point of view, quinoa is the best. These days, you can find rice, corn and buckwheat breads and pastas in larger supermarkets and good health-shops.

There’s no gliadin in oats. If you are gliadin-sensitive, then you can eat oats, but not wheat, rye or barley. Oats also contain potent anti-inflammatory compounds.

If you are only wheat-sensitive, it’s relatively easy. Just eat rye, barley or oats. For example, you can eat rye bread, oatcakes and oat-flake cereals, but not Weetabix or wheat bread.

In the big scheme of things wheat’s prominence as an allergen shouldn’t be surprising. Grains are the second most recent addition to the human diet, and weren’t eaten by hunter-gatherers. They were eaten by farmers for something like the last 10,000 years, but only in certain parts of the world. For example, no gluten grain naturally grows in North-America, so Native Americans have been exposed to gluten for only about the last 200 years at most.

A worrying trend in the US, where ‘low-carb’ diets are the craze, is to remove the carbohydrates from wheat products so you’re just eating the protein portion. As this is principally gluten, it’s a recipe for disaster for anyone with a hidden gluten allergy.


Some people are allergic to egg white, but not egg yolk. If you are sensitive to eggs, when you come to reintroduce them, it’s best to start by reintroducing egg yolk. If you don’t react withing five days, then reintroduce egg white. Eggs are in quite a lot of processed foods and bakery items, so check the label carefully.

Nuts and beans

These are part of the same food family, along with fruit pips. In essence, they’re all seeds. The most common individual allergens in this group are, in descending order, cashew nuts, Brazil nuts, almonds, peanuts, haricot beans and soya beans. You can react to one and not the others, but if you do react to a member of this family there’s a greater chance that you’ll react to another member of the pip/bean/nut family. Coffee, from the coffee bean, and chocolate, from the cocoa bean, are also members of this family.


Another major allergen is fish, but most people who are allergic to it react to white fish, not the oily fish such as salmon, mackerel and herring that are so rich in omega-3s. If you’re also allergic to those kinds, however, take a tablespoon of chia seeds with breakfast every day, together with a good-quality supplement, to keep your essential fatty acids topped up.

Shellfish allergies are very common, with prawns and abalone two of the worst villains. You may be allergic to mussels, scallops, whelks, oysters and squid, which are molluscs – or to lobsters, crayfish, prawns and shrimps, which are crustaceans. Octopus is in a world of its own! Be careful here, though. If you’re allergic to squid but not to octopus, be aware that some people sell squid labelled as octopus to make a bigger profit, because they can buy it more cheaply.

How the Holford Diet caters for you

If you suffer from food allergies, you don’t have to feel deprived on the Holford Diet. It is always sensible to vary your diet as much as possible, and the menu plans and recipes are designed to include a wide range of ingredients. Such a varied diet, together with the introduction of exciting new foods such as quinoa, soya products and lesser-used legumes such as flageolet and cannellini beans, ensures that there is plenty to tempt your taste buds, even if you do have to avoid certain items.

When you have an allergy test, the best laboratories will give you clear instructions on what not to eat and what you can eat, as well as giving you the back-up of a nutritionist to answer any of your questions. By avoiding foods that cause symptoms, you will probably find improvements in your health that you didn’t ever imagine. I can’t count the times I’ve heard people say, “I didn’t even know I could feel this good.” The Holford Diet and supplements will also help to further reduce your allergic potential.

After three months of abstaining from the allergen, you may then find that you can tolerate it in small periodic ‘doses’. For some people the allergy disappears completely. Others have to be careful about certain foods for life. Once you have more than a sneaking suspicion that you are allergic, it is best to have an allergy test.

Once you’ve identified what you are allergic to, and eliminate it, the next step is to improve your gut health. I recommend having a heaped teaspoon of glutamine powder in water last thing at night to help heal the gut, plus a probiotic supplement containing dairy and sugar-free acidophilus and bifido bacteria to help restore gut health. These are only necessary for a couple of weeks after eliminating your offending foods to restore gut health and reduce your allergic potential.


  • Find out if you are allergic to something you’re eating and avoid it. You can do an avoidance/reintroduction test but, quite frankly, it’s better to have a proper ‘quantitative IgG ELISA’ test.
  • After three months you can reintroduce the foods you tested positive for, although ideally not eating them every day.
  • Even if you are not allergic to it, reduce the amount of cow’s milk you eat and drink, substituting goat cheeses, soya produce and the like.
  • Even if you are not allergic to it, reduce the amount of wheat you eat, substituting other grains such as oats, rye and rice.
  • Limit alcohol. Ideally drink no more than three small glasses of wine, half-pints of beer or lager, or single spirits a week.
  • Drink the equivalent of eight glasses of water a day.

Patrick Holford’s The Low-GL Diet Bible

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