Dairy foods—such as milk, cheese, yoghurt, and butter—have long been part of traditional diets around the world. They are valued for their calcium, protein, fat-soluble vitamins, and energy density, particularly in growing children and older adults.

However, dairy tolerance varies widely. While some people digest and thrive on dairy foods, others experience digestive discomfort, inflammation, or respiratory symptoms. Understanding how dairy affects the body helps individuals make informed dietary choices.

Nutritional Benefits of Dairy

Dairy foods can provide:

Calcium for bone and teeth health
Protein for muscle maintenance and repair
Vitamin B12 for nervous system function
Fat-soluble vitamins (A and D), particularly in full-fat varieties

Fermented dairy products such as yoghurt and kefir also contain beneficial bacteria, which may support gut health in people who tolerate them well.

Digestive and Immune Considerations

Not everyone digests dairy easily. Common issues include:

Lactose intolerance, where the body lacks sufficient lactase enzyme to digest milk sugar
Protein sensitivity, particularly to casein
Immune or inflammatory responses in susceptible individuals

During periods of stress or illness, digestion may be compromised, making heavier foods like dairy harder to tolerate.

Dairy, Mucus, and Respiratory Health

Dairy foods are often associated with increased mucus or congestion, especially during respiratory infections. While scientific evidence is mixed, many people report thicker mucus or worsened congestion after consuming dairy when unwell.

One theory is that dairy can irritate mucous membranes or slow lymphatic drainage in sensitive individuals, prompting increased mucus production as a protective response. For this reason, naturopathic practitioners often suggest temporarily reducing dairy intake during colds, sinus infections, or tonsillitis, then reintroducing it once symptoms resolve.

Raw vs Pasteurised Dairy

Raw dairy is sometimes reported as easier to digest due to its natural enzymes and beneficial bacteria. Some individuals tolerate raw milk better than pasteurised forms. However, raw dairy still contains lactose and casein and may not suit those with sensitivities. Safety considerations also apply, particularly for children, pregnant individuals, and those with compromised immunity.

Dairy and Bone Health

Dairy is commonly promoted for bone health due to its calcium content, but bone strength depends on multiple nutrients, including vitamin D, vitamin K2, magnesium, and adequate protein, as well as weight-bearing exercise.

Calcium can also be obtained from many non-dairy sources, making dairy helpful but not essential for strong bones.

Alternatives to Dairy Foods

For those who avoid or limit dairy, alternatives include:

Plant-based milks (almond, oat, coconut, rice)
Goat’s milk or sheep’s milk, which may be easier to digest for some
Calcium-rich plant foods such as leafy greens, sesame seeds, almonds, sardines, and legumes

Choosing unsweetened, minimally processed options helps maintain nutritional balance.

Dairy and congestion

There is a lot of supporting data concerning dairy foods contributing to a worsening of symptoms in tonsillitis; however, there are no strong conclusions formed or studies done to substantiate this. Most people find that dairy foods do in fact contribute to mucus production and a worsening of the congestion when there are respiratory infections present. Naturopaths will always suggest excluding dairy foods when there is a respiratory infection present.

A few reasons why dairy can contribute to mucus production:

Dairy foods are quite acidic and contribute to inflammation by reducing waste removal in the lymphatic system and cause irritation to the mucus membranes. The membranes then produce more mucus as a defence against irritation to help protect the linings of the respiratory tract.
The digestive system is compromised when the body is fighting an infection and this means that foods which require more energy to digest, such as dairy foods, place a bigger strain on an already weakened digestion. By reducing the amount of dairy foods you consume you are able to support the immune and lymphatic system to recover and reduce congestion.
Dairy foods add to the production of secretions by coating an infected place (such as the tonsils) and increase the amounts of wastes due to the proteins in the milk not being properly broken down
Dairy foods contain the sugar lactose which is often a problem for many people in regards to allergies and intolerances. If the body is unable to break down this sugar an immune response is activated which can cause immune weakness, sensitivity and the production of inflammation and mucus

Individualised Approach to Dairy

Dairy is neither universally beneficial nor universally harmful. Some people thrive on dairy, while others feel better without it. Paying attention to digestive comfort, skin health, respiratory symptoms, and overall wellbeing can help guide individual choices.

Dairy foods can be a valuable source of nutrients, but tolerance varies greatly. Listening to your body, adjusting intake during illness, and exploring alternatives when needed allows for a flexible, balanced approach to nutrition that supports long-term health.

Dairy Foods: Benefits, Considerations, and Individual Tolerance