The Diet Detective Method is most suited to diet investigation where an initial elimination diet is not known so a best-fit or suggested diet is used. The Method is used for a trial time, usually four weeks, and any changes in symptoms noted. Then detective work continues assessing the outcome when various foods are reintroduced—which we call ‘challenges’. The diet detective method is clearer now but it has been developing over the last forty years. Not everyone reacts to the suspect food chemicals so clarifying whether you react is another benefit of the diet detective method. A good example of the Diet Detective Method is the process provided in the book Your Diet for Your IBS, from this site.
The idea of diet detective work began in 1975 when I worked closely with 75 families helping their hyperactive (now ADHD) children to try a diet low in additives and salicylates. We wanted to see if it would decrease their symptoms and to work out which foods they could tolerate and which caused reactions. To convey this investigatory sense I used the words “being a diet detective”.
Most of my patients were hyperactive boys. I wanted them to understand having to investigate what foods they would have to stop eating for a while and then start eating again and see if symptoms reoccurred. Their knowledge of storybook or TV programs about police detectives finding things out helped them understand what they were doing.
I had an open mind as a scientist and I encouraged the families to keep an open mind also. It was an exciting and interesting time for all of us.
At a different level I was also investigating just which symptoms changed and how much they changed, and which children responded to the diet and which did not.
I gradually realized I needed to apply the diet detective method to the diet itself.
The initial diet was defined by Dr Ben Feingold. His claim that additives caused hyperactivity was controversial. His Feingold diet was based on a low salicylate diet used by dermatologists—but he also excluded additive colours, flavours and preservatives. That diet was based on salicylate analysis data done in 1922!
The medical profession challenged Feingold’s theory that his diet cured hyperactivity. Most researchers did this by putting the families with hyperactive children on the diet as defined by Feingold for a time, and then off the diet, or they devised two fairly similar diets and then they challenged by changing from one to the other. They showed that additives did not cause hyperactivity in all children, but that the diet did usefully help some hyperactive children.
As well, different clinical researchers applied the diet to their practice and published their findings. They each altered the diet itself where the feedback from families provided information about what foods diet-responding children reacted to.
I eagerly read published papers from the several groups who published their clinical findings. Some began with a very strict diet, such as the “Few foods” diet and after four weeks challenged with various single foods and additives. Even though they each adjusted the elimination diet they provided so the initial diets were not exactly the same, all researchers lowered the total load of the suspect chemicals and showed that diet produced statistically significant change in some children. Chocolate, carrots and sugar were additional suspect foods. All researchers and I reported that the Low Additive, Low Salicylate, Amine and Glutamate Diet reduced other symptoms as well as ADHD. These extra symptoms included migraine, irritable bowel syndrome (IBS), chronic headaches, allergic conditions such as eczema, asthma, hay fever, rhinitis, hives, mouth ulcers, reflux. See the full list in Your Diet for Your IBS.
In the 1980s, I began diet investigation using the “Test” diet free of additives and salicylate. Using the detective concept, I worked with my patients and the Qld Hyperactivity Association. I had new salicylate data from Dr Anne Swain’s careful research. However, the diet detective method was reinforced by having families test the findings and learning that the tolerance of foods such as apples did not consistently follow the analysis data. Some foods consistently caused reactions, even when research suggested those foods were low in salicylate.
Over time many families used the diet detective idea to implement a diet to see if it helped their child and what improvements it produced. I noted which foods caused most reactions and should be excluded from the initial elimination diet, and recorded challenges that could be used to test each additive without being confused with another suspect additive or salicylate. Chocolate, an amine, as well as MSG, were implicated and also excluded, as were milk and wheat in some. As well as artificial flavours, all aromas, including all smells, need to be minimised in the initial diet. Following the ‘detective’ theme, I called these foods and chemicals the ‘usual suspects’—as they were often the culprits creating the problem in the children!
I learned that foods reported to cause reactions in the three generations of the person investigating diet were best excluded from the elimination diet. So parents and kids had to search for ‘clues’ in their family history—finding aunts and cousins with similar problems.
Over time, various analysis data on salicylates has shown variability in amounts present in foods. Unfortunately, this means there cannot be charts for salicylates which are exact, as there are for lactose or gluten in foods. Amines are important but vary greatly with storage and age, and glutamates also vary. As well there is great individual variability in people in what is tolerated.
Together these factors mean that using the diet detective method is the ideal approach to apply when diet investigation is promising, but where a specified diet is not clear. A personalised elimination diet can be devised, implemented for around four weeks and challenges used to clarify what foods are tolerated in amounts and frequency that means as many foods can be used as possible. Like detective work, it’s all about following the clues, working out what’s possible, and getting to a good result.
Link to my review article The Role of Diet and Behaviour in Childhood https://foodintolerancepro.com/category/evidence-base/the-role-of-diet-and-behaviour-in-childhood/
Link to my thesis https://foodintolerancepro.com/product/thesis/