Food Sensitivities: Signs and Symptoms

What are food sensitivities?

Do you eat and begin to feel sluggish, tired, or fatigued shortly after? Do you feel itchy or irritable after eating?

If you answered yes to these questions, it’s a possibility you have hidden food sensitivities. One of the most surprising aspects of food sensitivities is that sometimes healthy foods are causing the problems. It might be the foods you are least likely to suspect that are causing you the most discomfort.

Food sensitivities trigger reactions in the body, therefore delaying immune system response. This delayed response makes it more difficult to discern which foods are causing problems, because the issue isn’t occurring directly after eating the problem-food. If you ate a problem-food in the morning, and don’t feel symptomatic until bedtime, it can be hard to pinpoint what is causing your symptoms.

We’ve put together a list of the most common food sensitivity symptoms. If you are experiencing most of these symptoms, a food sensitivity test or elimination diet can help give you in depth information on what’s affecting your body.

Signs of Food Sensitivities

Sudden Weight Loss or Weight Gain

Are you having difficulties maintaining a healthy weight without any sudden diet changes? Sudden changes in weight while keeping a stable and steady diet can indicate food sensitivities. A bloated appearance or weight gain can be inflammation in disguise. Getting rid of the unwanted weight requires removal of the problem-foods and healing the gut. Read more on reducing inflammation here.

ADHD or Hyperactive Behaviors

The rates of ADHD are rising with 1 out of every 10 children diagnosed with ADHD. This disorder also affects adults. Adults and children with ADHD-like symptoms oftentimes don’t realize their symptoms are linked to diet choices. Symptoms such as foggy brain, lack of focus, hyperactivity, anxiety, fidgeting, impulsive behaviors, and mood swings can all be related to inflammation resulting from the body’s reaction to food sensitivities. Nutrients broken down in the gut influence our production of neurotransmitters. Nutrient malabsorption occurs after eating problem foods, creating ADHD behaviors due to sacrificed neurotransmitter production. Click here to read more about ADHD and MTHFR mutations. 

Anxiety and Depression

As mentioned above, neurotransmitter production is influenced from the nutrients, proteins, and amino acids broken down in the gut. Without optimal amounts of dopamine and serotonin, due to digestive problems within the gut, anxiety or depression may occur. Click here for an MTHFR friendly supplement that supports Serotonin synthesis. 

Once the problem-food is removed from the diet, and inflammation is reduced, anxiety and depression can be resolved. Symptoms of anxiety include: tense, foggy brain, lack of focus, panic, weakness, lack of control, breathing problems, irregular heartbeat, panic, and chest pains. Symptoms of depression include: lack of interest, hopelessness, anxiety, changes in mood, trouble sleeping, changes to appetite, and lack of energy. Learn more on improving anxiety here. 

Foggy Brain

Foggy brain, or the inability to think clearly, can be highly frustrating. Many people with food sensitivities mention feeling “out of it” or “less sharp”. The reactions triggered by food sensitivities can create inflammation. Chronic inflammation can lead to chronic brain fog and some individuals may have difficulty remembering recent events, recalling names, or find themselves staring blankly off into space for extended periods of time. One of the biggest complaints with food sensitivities: after eating many individuals feel brain fog or a lack of focus which  can affect work/school performance. Find out how COQ10 improves brain fog and chronic fatigue here. 

Skin Issues

Food sensitivities can cause many different skin reactions such as eczema, hives, psoriasis, rosacea, itchiness, burning, and redness. When the gut is exposed to chronic inflammation, these reactions are more likely to occur.  Food sensitivities can contribute to leaky gut. Leaky gut, or gut permeability, allows gut bacteria, yeast, and undigested food particles to enter the bloodstream. One common complaint with Leaky gut, are skin issues.


Inflammation from food sensitivities contribute to chronic headaches. There are many cases of individuals who take Advil or Tylenol around the clock, hoping for relief from the headaches. Food sensitivities don’t cause all headaches, but if you are constantly consuming a problem-food, headaches are one of the most painful and common symptoms. For some chronic headache sufferers, simply avoiding the problem-food can reduce headaches. Another healthy pain reliever and headache reducer alternative is Magnesium. 

Low immune system

Have you noticed that you get sick more often than others? Food sensitivities could be one contributor to a poor immune system. With food sensitivities, the body delays immune reactions resulting in lower levels of antibodies. These antibodies are needed to defend your body against bad bacteria and increase your susceptibility to illness. For additional immune system support through supplementation, click here.

Stomach problems  

One of the most common symptoms of food sensitivities are gut problems. Many individuals feel nauseous, bloated, cramps, constipation, diarrhea, or stomach aches. These symptoms are extremely uncomfortable. This can occur because of inflammation from the problem-foods or as a symptom of leaky gut.

What can you do?

The best way to figure out your food sensitivities is through an IgG Food Sensitivity Test. Another option is an elimination diet, this is when common inflammatory foods are removed from the diet to see if symptoms lessen. The problem with elimination diets: only certain foods are removed and finding the right combination of food sensitivities takes time. IgG Food Sensitivity Tests give a comprehensive analysis of many different foods to give you a clear result of all the foods causing you symptoms. Click here to test for 184 foods. 

Click here to schedule a free 15-minute consultation call with our MTHFR Experts. We are happy to answer your questions and to help you get on the right path towards feeling better.

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