If this is one of your SymptomQuiz high scores, the information in this article may help you improve your Wellness Score. There are many herbs and nutrients that have been shown to reduce histamine, reduce inflammation, and support the immune system. Presenting a complete list with the literature references may be a bit unwieldly. Several reputable companies produce combination products. First, follow the Roadmap to Health diet. Supplementation should be secondary.

Quick cookbook: Follow the Roadmap to Health diet. Take Quercetin and vitamin C—one of each, 2x/day. Read more about the Quercetin/Vitamin C combination.

Allergies are commonly treated as isolated problems—itchy eyes, sinus congestion, or skin reactions—but in many cases, they reflect broader imbalances in the body. While symptom relief is often the focus, it does not explain why the immune system is reacting in the first place.

A wide range of nutrients and botanical compounds have been shown to influence histamine, inflammation, and immune activity. However, focusing only on supplements can miss the larger issue. Diet and underlying physiology tend to play a more central role, and supplementation works best as a secondary strategy rather than the primary approach.

What Drives Allergies?

Allergies are often linked to multiple contributing factors rather than a single cause. Chemical exposure, repeated use of medications—especially antibiotics—poor diet, and hidden food sensitivities can all increase the likelihood of immune reactivity. These factors do not act in isolation, but together create a pattern that predisposes the body to overreact. This helps explain why some individuals respond quickly to basic changes, while others require a more comprehensive approach.

Diet and Hidden Food Sensitivities

Diet is one of the most consistent variables in allergy patterns. Many individuals react to common foods such as grains, dairy, or soy, but these reactions are often delayed and difficult to identify. Unlike immediate allergic responses, these sensitivities may take up to 72 hours to appear, making them easy to overlook. In many cases, the foods causing the problem are eaten frequently, which makes them even harder to recognize.

This pattern was described in detail by Theron Randolph, who observed that individuals are often sensitive to foods they consume regularly, and that the foods driving symptoms are sometimes the ones most strongly craved. When these foods are removed, symptoms may initially worsen before improving, a pattern that has been observed clinically for decades.

Digestion and the Microbiome

Digestive function plays a central role in allergy development. When food—especially protein—is not properly broken down, it can alter the microbiome and contribute to immune activation. Disruption of bowel flora and increased intestinal permeability have both been linked to allergic conditions [12,13]. Many practitioners have also observed that low stomach acid (hypochlorhydria) may contribute to allergies. While research in this area is limited, the mechanism is plausible: incomplete digestion may promote dysbiosis, which in turn influences immune reactivity.

The gut microbiome is closely tied to immune balance. When the normal bacterial environment is disrupted—whether from antibiotics, poor diet, or other stressors—the immune system can become more sensitive and reactive. This helps explain why allergies often develop after repeated antibiotic use or long-term dietary stress, and why restoring microbial balance can play an important role in improving symptoms [5,6].

The Liver Connection

There is also evidence suggesting a connection between liver function and allergic responses. The liver plays a central role in processing chemicals and toxins, and when this system is overwhelmed, the body may become more sensitive to environmental exposures. Early observations noted improvements in allergy symptoms with liver-derived compounds [9], and more recent research has explored links between liver pathology and immune sensitization [5]. In transplant medicine, cases have been reported in which recipients develop allergies similar to those of the donor [7,8], suggesting that immune patterns may be influenced by systemic factors beyond simple exposure.

Antibiotics and Immune Dysregulation

The relationship between antibiotics and allergies has been explored in multiple studies. Antibiotic use can alter the microbiome in ways that promote immune imbalance, and research has linked antibiotic exposure with increased allergy risk [10]. In some cases, antibiotic therapy has been shown to perform no better than placebo in preventing recurrent sinus symptoms [11]. These findings highlight the importance of microbial balance in immune regulation.

Nutritional Support: Helpful, But Secondary

There are a number of nutrients and botanical compounds that have been studied for their effects on allergic symptoms. These can be helpful, particularly when symptoms are more pronounced, but they tend to work best when combined with dietary changes and support for digestion and the microbiome.

One of the most commonly used combinations is quercetin with vitamin C, which is often used to help stabilize mast cells and reduce histamine release (see: Quercetin/Vitamin C article).

Other nutrients have also been studied. Vitamin A plays an important role in maintaining the health of mucous membranes, including the eyes and respiratory tract [1–3], and may be helpful in individuals with symptoms such as dry or irritated eyes. Methylsulfonylmethane (MSM) has been associated with improvements in seasonal allergy symptoms, including congestion and itching [4]. Probiotics, particularly strains of Lactobacillus and Bifidobacterium, may help regulate immune responses and have been studied in conditions such as eczema and food sensitivities [5,6].

The overall approach is simple: the Wellness Plan focuses on the Roadmap to Health diet as the foundation, with one or two targeted supplements added when appropriate. This keeps the focus on restoring function rather than simply managing symptoms, and tends to be more effective than taking multiple products at once.

The Big Picture

Allergies are not simply the result of exposure to allergens. They reflect a state in which the immune system is more reactive than it should be, often due to multiple underlying factors. Addressing diet, digestion, microbiome balance, and environmental exposures tends to have a more lasting effect than focusing on symptom suppression alone. Nutritional and botanical support can be useful, but they are most effective when used as part of a broader strategy.

(Educational only—not medical advice)

Selected References:

  1. Mediators Inflamm. 2018 Aug 9;2018:3067126. Impact of Retinoic Acid on Immune Cells and Inflammatory Diseases
  2. Community Eye Health. 2013;26(84):66–67. The eye signs of vitamin A deficiency
  3. Drug Des Devel Ther. 2017 Jun 23;11:1871–1879. Efficacy and safety of retinol palmitate ophthalmic solution in the treatment of dry eye: a Japanese Phase II clinical trial
  4. JMIR Res Protoc. 2018 Nov 29;7(11):e11139. Evaluating the Impacts of Methylsulfonylmethane on Allergic Rhinitis After a Standard Allergen Challenge: Randomized Double-Blind Exploratory Study
  1. Pediatr Allergy 2012 Dec;23(8):771-8. doi: 10.1111/pai.12011. Epub 2012 Oct 11 High prevalence of food sensitisation in young children with liver disease: a clue to food allergy pathogenesis?
  2. 2021 Mar 25;10(4):701. Probiotics as a Possible Strategy for the Prevention and Treatment of Allergies. A Narrative Review
  3. Ann Hepatol. 2019 May – Jun;18(3):508-513. doi: 10.1016/j.aohep.2018.10.006. Epub 2019 Apr 15. Transfer of peanut allergy from donor to recipient after liver transplant. Aggarwal A, Balogun R, Carr TF, Desai AP, Jie T, Pan JJ.
  4. 2019 Nov;103(11):2338-2346. doi: 10.1097/TP.0000000000002751 High Frequency of Concomitant Food Allergy Development and Autoantibody Formation in Children Who Have Undergone Liver Transplantation. Käppi T, Rabe H, Lingblom C, Hesselmar B, Kullberg-Lindh C, Wold AE, Wennerås C, Saalman R.
  5. https://www.jstage.jst.go.jp/article/tjem1920/13/5-6/13_5-6_461/_article/-char/ja/ Link to Japanese research from 1927
  6. (PLoS Pathog. 2010 May 27;6(5):e1000549). The Microbiota and Allergies/Asthma
  7. Pediatrics (April 2001;107:619-625) Diagnosis and management of acute rhinosinusitis in children
  8. J Allergy Clin Immunol. 2012 Jun;129(6):1452-9;