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What is the Difference Between a Food Allergy, Food Sensitivity and Food Intolerance? And What are the Best Tests?

Many of my patients ask me about food allergies and what the best tests are. I thought I'd write an article to clarify. There has been a sharp rise in food allergies and I've noticed many urban restaurants now have gluten free options. Servers will often ask a party if there are any food allergies before taking orders. More people are much more conscious of food sensitivities. In fact, there are studies showing links between food sensitivities and difficulty losing weight, autoimmune diseases, and gastrointestinal diseases. Some patients achieve some type of relief by avoiding certain foods.

However, I've seen patients who are so sensitive that the list of foods they can tolerate is so small, that their quality of life does not seem so fun. I feel it is important to identify food sensitivities and avoid them for a period of time to allow the body to calm down. I do not feel that it is optimal for a person to be permanently "allergic" to say 50% of all foods tested. This often means that there may be intestinal permeability issues that allow too much exposure of food antigens to the immune system. In these cases, it is very important to also work on improving intestinal health as well as immune modulation in addition to working with food allergies.

More information on food allergies, sensitivities, intolerances and testing options are below.

Food Allergies:

IgE Food allergies occur when the immune system makes antibodies to foods. This is a very specific reaction like a lock and key. If the antibodies made are IgE antibodies, the reaction is usually immediate. These reactions can be immediate fatigue, immediate hyperactivity, swollen lips, abdominal discomfort and respiratory symptoms. An IgE mediated reaction is what we classically call a food allergy. Usually anaphylactic reactions fall into this category.

If the antibodies produced are predominantly IgG antibodies, the reaction is often delayed sometimes 24-48 hours after eating the offending food, making it more difficult to pinpoint a correlation. Sometimes the symptoms that show up may be subtler, such as poor concentration, chronic respiratory symptoms, chronic behavioral issues, and frequent illness.  These non-distinct reactions make it difficult for people to realize that they have a food allergy but knowledge of this can be very helpful. For example, people with chronic diseases such as autoimmune diseases, chronic pain and inflammation, allergies, asthma, headaches, itching and fatigue tend to have underlying food allergies.

Food Intolerances:

Food intolerances occur when the body lacks enzymes to digest a certain type of food. A classic example of an intolerance is lactose intolerance, where an individual lacks the enzyme lactase that breaks down lactose, a sugar found in dairy products. Thus people with lactose intolerance usually will have symptoms such as abdominal pain, flatulence, diarrhea or fatigue when consuming milk products. A lactose intolerant individual may also have an allergy to milk in addition to the intolerance. People who have an intolerance often feel better by avoiding the food, but in mild cases can consume the food with a digestive enzyme given to help the body break down the food.

Food Sensitivities

This is a non-specific immune response to food. For example, white blood cells may swell, change morphology, or rupture in response to exposure offending agent. This is not an allergy because an antibody is not produced. These reactions are often harder to identify and may be an underlying problem contributing to weight problems, chronic disease, behavioral issues to name a few. These types of sensitivities often show up with an ALCAT testing when a skin prick test or RAST test is negative. 


Skin prick allergy tests usually measure IgE antibodies. They are very good for detecting environmental allergens and some food allergies that tend to be more severe such as peanut allergies. Skin prick tests are generally not good tests to test for foods because they often show false negative results. A RAST test is a blood IgE test that may be more accurate for foods than a skin test.

IgG blood tests give some additional insight and show allergies that are subtler and delayed. These reactions still trigger an inflammatory response that is usually not as acute or obvious. But this chronic low-grade inflammation can be enough to release enough inflammatory chemicals that can cause more oxidative damage to the body.

The gold standard for finding problematic foods is the elimination challenge test. Patients restricted to 4 non-allergenic foods for 2 weeks, then re-introduced one food at a time and monitored for reactions. Data shows this is more accurate than any of the laboratory tests. However, this is often difficult to do and very labor intensive.

ALCAT Laboratories offers a blood test that measure the change in size of white blood cells when exposed to certain foods, thus measuring the immune reaction to the food, rather than anti-bodies. The immune system can react to what it perceives as an intruder without making antibodies. This test is personally my favorite test and seems to be much more clinically relevant than the RAST test. A study done at the Department of Pediatrics in Pavia Italy showed that patients with gastrointestinal symptoms who tested negative for allergies (skin prick, and RAST), when following the ALCAT food elimination had improvements in their symptoms. ALCAT tests picked up what some of the other tests did not. Another study showed that patients who were unable to lose weight on a low calorie diet, who followed the diet plans according to their individualized ALCAT tests observed significant decrease in body weight according to the Middle East Journal of Family Medicine. Lastly according to the Medical School of Cape Town Africa, ALCAT testis high a high degree of reproducibility.

Some doctors such as myself will also use kinesiology or muscle testing in addition to the blood tests. I sometimes find that muscle testing gives more accurate results than any one of these blood tests used alone, and I postulate that muscle testing combines all types of reactions the body has to the food, as we attempt to energetically get information from the body.

According to Dr. Mark Hyman MD, these are symptoms to look for if you suspect a reaction to certain foods. Many of these symptoms are generally not thought of in relation to a food, but can be a tell tail sign that there may be some benefit to finding out if you have any food sensitivities or intolerances. Many of these symptoms are vague and may be associated with other medical conditions as well, so consult your health care provider. 

Brain fog







Sleep problems

Changes in skin (acne, eczema, rash)


Joint/Muscle aches

Changes in digestion or bowel function


Respiratory congestion

Difficulty remembering things




Things You May Not Know About Immunity

Many of you may be worried about getting the flu or struggling with fighting illness after illness this season. Boston declared a state of health emergency earlier this January stating that there have been 700 cases of influenza compared to 70 last year at this time in Boston. The CDC estimates about 200,000 Americans get hospitalized per year for complications related to the flu; this is 0.06% of our 314 million population. Even though these numbers seem high for the flu, also be aware of the following statistics for adverse reactions from prescription drugs. According to the Institute for Safe Medical Practices May 2012 an estimate of 4 million people in the US suffered injuries associated with prescription drug therapy. 179,855 cases were reported to the FDA in 2011 of serious, disabling or fatal prescription drug events.

We want to do what we can to strengthen the immune system, but do not let fear overtake decisions for your health. Many Americans have been pressured to get the flu vaccine, and this has been made stronger by the media's creation of fear in the public. According to the Cochrane Review 2010 (Review of 50 articles and 36 clinical trials), healthy individuals may be discouraged to get the flu vaccine. The report states that in the case when the vaccine strain is well matched with that year's actual influenza viruses, that 1% of vaccinated people develop flu symptoms and 4% of unvaccinated people develop flu symptoms. This is not a very large difference. The flu vaccine does not seem to decrease complications from the flu or reduce its spread. The decision to vaccinate is personal and can depend on other factors. Know that keeping your own immune system strong is an alternate form of protection. Below are some considerations for you to muse over on how some food choices can affect the immune system.

Sugar: Have you even wondered about the correlation between sugar and getting sick? Think about the increased pediatrician visits for infectious illness after Halloween candy. Have you also wondered if perhaps all the holiday sweets contribute to tendencies to getting sick during the wintertime, among other factors? According to a study at the Loma Linda University, research subjects were given 100g of sugar (equivalent to 1L of soda). They drew the blood of the subjects and tested their blood for the ability to phagocytize bacteria. The blood of subjects who had the sugar, was less effective at destroying the bacteria than those who did not just have the sugar. This study showed that sugar eating did not decrease the number of neutrophils but decreased their responsiveness. Dr. Sears MD says that having about 8 tbsp of sugar can reduce the white blood cells ability to kill germs starting 30 mintues after to about 5 hours later by 40%.

Nutrition: Adequate nutrition is essential for a properly functioning immune system. Amino acids are building blocks needed for immune cells which are found in protein, not carbohydrates. Getting infectious diseases are often associated with an underactive immune system. Allergies are often associated with an overactive immune system. Dr. Leo Galland MD says, "It is important to understand that these two conditions (infection and allergy) often occur together. The problem is not usually that the immune system as a whole is too strong or too weak, rather, it is disorganized." He goes on to say that craving for sweets is often a sign of general nutritional deficiency. So load up with your proteins, vegetables and fruits, which contain vitamins and minerals, good fats such as EFAs, nuts, seeds, olive oil etc. and you will not crave the sugar, which lowers the immune system.

 Wheat: When discussing about allergies associated with infections, it is important to understand that many people have silent food sensitivities that evoke an "allergic like" response in the body. They create vague symptoms such as fatigue, gas, bloating, sleepiness after eating, headaches, brain fog etc, that do not manifest like a traditional hayfever allergic response or anaphylaxis. When there is a "silent food sensitivity/allergy" there is a higher correlation with susceptibility to infections as discussed above.

If I had to pick one food to watch that will positively affect a decrease in susceptibility to infection, I would decrease the consumption of wheat. Anecdotally, it seems that wheat in other European countries do not have as many adverse affects as the wheat in America. I wonder if it is because of the heavy genetic modification, the irradiation of wheat seeds with chemicals, gamma rays and X-rays that is more prevalent here? (See PMID 16143119 Natural variation in toxicity of wheat: potential for selection of nontoxic varieties for celiac disease patients. Leiden University Medical Center, Leiden, The Netherlands). According to the Mayo clinic, a wheat allergy is different than celiac disease. Many people may have a wheat allergy, but not celiac disease.

A study at the Bartholin Institute in Demark 2012 showed that gluten, a protein found in wheat increased a type of T cell associated with auto-immunity. A diet that contained gluten decreased gamma delta T cells. Gamma delta T cells have complex functions but are often thought of as the "first line of defense". There is much more research on the effects of wheat and autoimmunity compared to wheat and infectious disease susceptibility, however again the two have a common thread of immune dysregulation. And I see clinical benefit with my patients in reduction of wheat associated with reduced susceptibility to infection.

I work with patients who may want natural alternatives to anti-biotics for chronic sinus infections, or those who seem to catch cold after cold for example. Decreasing wheat and sugar have profound effects alone, and in some cases patients have a more profound response with some additional nutritional supplements that support their immune system based on their individual constitution.

This is not to say that all wheat and sugar needs to be avoided for a healthy individual. But there is a difference between someone who eats cereal, pastries, coffee and desert all day compared to another person who consumes lots of fruits, vegetables, protein and nutrient packed foods and then enjoys an occasional creme brulee. Lastly, get the rest you need, stay hydrated, and remember to smile. Have an awesome start to the New Year!


The Vis Medicatrix Naturae

What is the Vis Medicatrix Naturae?

This is Latin for the Healing Power of Nature and one of the naturopathic principles. When going through the healing process, one must trust that the body has an innate ability to heal. What we choose as an avenue to heal, whether it be diet, exercise, counseling, nutritional supplements, body work etc are used with a goal to support the healing power of nature which we will call “the Vis”. Someone with a stronger Vis will be able to recover with much more ease than someone with less Vis, given the same condition. But this does not mean that someone with a weaker Vis cannot build that up. This is one of the goals of naturopathic medicine.

The Vis is not just a physical life force, or strength. It is also emotional and spiritual. All aspects of life are tied in together. One leading cause of stress is not doing what aligns with one’s inner values. This discrepancy can cause one to feel internal tension. This situation can lower one’s Vis and make it more difficult to have the motivation to live a happy and healthy life. Success is doing what one believes in.

How do you measure or quantify it?

The bio-impedance analysis test BIA, which we run in our office is a way to partially quantify the Vis. Since it is an abstract principle, it is not something that can be completely quantified in all aspects but this test particularly quantifies more of the physical aspect of a person’s vital force.

The BIA machine measures capacitance, resistance, charge, body water etc. When a person’s cells can keep the membrane potential as negative as it should be, the cells function optimally. The machine calculates through a series of measurements something called a phase angle. The higher the phase angle, the stronger the person is, and better able to recover from illness quickly. Studies also show that the more muscle mass a cancer patient has, the higher their survival rate.

How do you influence the Vis?

There are many ways to to influence the Vis and generally this is what we go into detail with a naturopathic consultation. We find specific supplements to give your body the correct signals to heal. As we discussed above with BIA testing and the goal of creating healthy cell membranes, fish oils and vitamin D are some supplements that will achieve that.

From a mind body perspective the Vis can be enhanced by a loving relationship, healthy thoughts, discipline, healthy lifestyle etc. It can be drained out by just the opposite of the above. Sometimes freedom to do whatever one want feels good at first. However the unleashing of self to go after the type of pleasure that does not support one’s wellbeing eventually becomes binding and depletes the Vis. 

For example sometime it feels good to dwell on negative thought patterns, or to have yet another piece of sugary food after a difficult day. But if it does not align with your inner goal to be happy and healthy, then there is actually no freedom in the indulgence. True freedom is having the discipline to do what it takes to allow yourself to live the way you want to. Success is doing what you believe in. So give yourself the gift of encouraging the Vis Medicatrix Naturae within yourself and remember to give thanks for what you already have abundantly.



How Does Stress Affect the Gut and Sleep?

We have all heard phrases like, "I have butterflies in my stomach" or "I just go with my gut" or "My stomach really does have a mind of it's own". From a sociological standpoint, we all instinctively know that there is a connection between the gut and the brain. The medical applications would be significant if this were true. But is it true? Can this link be scientifically validated?

Before we talk about the link between stress and the gut, let's talk a little about stress. Not all stress is bad. There is good stress called eustress which is essential to keep us motivated and have the physiological energy to wake up in the morning. Good stress provides a healthy challenge. Stress is damaging when the physical body cannot compensate, or when the mind percieves the situation as overwhelming.

For example, disrupted sleep is a stressor to the body and can change cortisol levels throughout the day contributing to symptoms of anxiety, fatigue and depressed mood. Research shows that 3 nights of disrupted sleep is enough to elevate cortisol at night which further perpetuates sleeplessness. Changes in cortisol levels can result in increased inflammation in the GI tract, increased cravings for sugar due to imbalances in insulin, and a slowed metabolism which may contribute to weight gain.

You may begin to see that this begs the "chicken or egg" question. I usually work with my patients to break these unhealthy cycles. The benefit of naturopathic medicine is that we work with each person's individual physiology. So rather than giving one pill that sedates you for sleep, but does not promote a restful and refreshed feeling in the morning, I use gentler and more specific therapies. Non invasive is sometimes misnomered as weaker, however, when used appropriately, they can have profound effects. For example melatonin is great for an inability to fall alseep, but it does not work for people who wake up multiple times during the night. There are some herbs that work much better for this other type of insomnia.

Stress and Increased Intestinal Permeability

So for those of you who are interested in the scientific link between stress and the gut, this is how it works:

  • Stress triggers the limbic system of the brain to release CRF and ACTH
  • CRF and ACTH travel to the adrenal glands where they stimulate release of cortisol and adrenaline
  • Cortisol and Adrenaline can activate immune cells that live in the gut wall to burst. These cells are called mast cells and release histamine when they burst.
  • Histamine stimulates the lymphocytes (immune cells) to start fighting, leading to an inflammatory response. The inflammed tissue in the gut is less intact and becomes more permeable, allowing particles that should stay in the gut, to leak out to the blood stream. When these foreign particles leak out to the blood stream, they further trigger more of an immune system reaction in the rest of the body.
  • This is how intestinal permeability can lead to auto-immune and allergic processes. This also explains how stress increases inflammation in the gut itself, leading to symptoms such as bloating, diarrhea, constipation, intestinal pain, mucous in the stools, etc. 

How to Help?

It is important to consider these principles when addressing intestinal health:

  • Remove (stressors, mibrobes, toxins and allergens)
  • Repair damaged intestinal mucosa
  • Restore healthy, beneficial bacteria that are essential to keeping the immune system balanced
  • Replace any necessary enzymes, HLC, or bile salts that may be deficient

Again being specific is important as studies show that certain probiotics in different dosages are more effective for certain conditions than others. I have patients who take the most common Accidophilus without much improvement, therefore it is helpful to seek professional help if your symptoms are not resolving. When used approprately, good quality nutritional supplements work well. My goal as a naturopathic doctor is to help promote your body to heal itself. Remember, our bodies are designed to be well. They have built in mechanisms to heal. It is when we suppress symptoms, emotions, or the body's cry for attention, that we push ourselves into more chronic sickness. When we address what is getting our attention, face it, love it, show it compassion and take steps to support healing, you'd be surprised at how resilient your body is.



To Eat or not to Eat...That is the Question

How does our attitude about food affect how successful we can be to achieve a healthy weight?

Angelina comes home from work at 8:30pm. Her team at work has successfully completed a month long project today and all she wants to do is to go home, have a couple glasses of wine, some comfort food and desert to reward herself. She is 5'6 165lbs. She used to be 130lbs when she was younger, but the weight has slowly crept up over the years. She has tried various weight loss programs and has been able to loose 20-25 lbs or so, but she seems to always gain it back. Why? What are some obstacles to her keeping the weight off? 

Growing up, Angelina's mom always rewarded her for good behavior with ice cream. Her mother would have lots of cheese and crackers if she was having a bad day to soothe herself. If she was having an especially bad day, she would say to her daughter, "Mommy's tummy looks so fat. I wish I looked like you. You make sure you don't eat too much so you stay pretty."

Many of my patients and friends believe that the less they eat, the less they weight. Calories in = Calories out. But that is not true. When you consume a food with less calories, for example a plain bagel, 70 calories (Panera Bread plain bagel 290 cal), compared to 2 eggs, 170 calories; it is natural to choose the bagel with 70 calories because it has the lowest calories. However the bagel is a carbohydrate, which means if you don't burn it, it gets converted by the liver into fat. The egg is protein and has much less of an effect on weight. Also, the bagel has almost no nutritional value, so when you consume it, your body is still asking you for more food, because it is nutrient deficient and you are more likely to crave more food after consuming the bagel. A study shows that people who consume zero calorie beverages are more likely to gain weight in 1 year than people who drink non-diet drinks. That is not to say that I am advocating for sugary non-diet drinks, but the zero calorie drinks may be worse because of the chemical effects the artificial sweeteners have on your brain, programing your brain to crave more food, because it is empty nutrition. Every type of food sends a different signal to your metabolism, so choose foods that are nutrient dense, and your brain will get the signal that you are satiated. This will help reduce cravings.

Another tendency I see is that people believe that the less they eat, the less they weigh. So especially with my busy patients, this is both convenient and works with their innocently misguided beliefs. Many people will have a coffee and skip breakfast, then have a light lunch at noon and not eat for 8 hours till they get back home from work. By that time they are starving, and will binge on foods for the rest of the evening. They often tend to eat more than they would have, if they had eaten nutrient dense meals and snacks during the day when the point of "hunger to no return arrives". Nutrient dense foods such as good quality proteins and healthy fats induce a chemical called somatostatin, that makes you full. Therefore, having these foods combined with fruits and vegies (which generally have zero effect on your weight), will help you feel full and reduce cravings. When you are overly hungry, your blood sugar drops very low which sends a message to your brain to eat the fastest thing that will elevate your blood sugar. That would be sugar and carbohydrates! But these foods will turn into fat if you don't burn them. So please eat breakfast and it is generally healthy to have some food every 3-4 hours.

Lastly with popular culture, we have often associated the word diet with beauty and restriction of food. This can have profound psychological effects on us when we view food this way. Hippocrates said, "let food be your medicine". So perhaps instead of thinking about restricting foods or calories; what if the paradigm was shifted to, "what foods can I choose to have more of, that nourish my body". And if you have more of nutrient dense foods, you probably would just naturally be more full and not want foods that do not support your body. I believe we all should live life, so do not feel bad if you ocassionally have deserts, or choose whatever you like when you eat out. Let's not punish ourselves with guilt that should not be. Rather let us be educated and make decisions that support our wellbeing. If you generally had 80-90% healthy foods, you would feel quite well. If you have 60% or more vegetables and fruit on your plate, you would also feel quite well. So to eat or not to eat, I'd say eat with gratitude.