A functional nutrition guide to popular diets and personalized nutrition

By Dr. Nathalie Beauchamp, DC

“The best diet isn’t the trendiest one—it’s the one that helps your body function at its best.”

One of the most common questions I get from patients is:

“What’s the best diet to follow?”

The short answer is….

It depends.

There isn’t one eating pattern that’s right for everyone. Your ideal diet depends on your genetics, lifestyle, health goals, digestive health, metabolic function, activity level and even your gut microbiome.

From a functional nutrition perspective, food is much more than fuel—it is information. Every meal you eat influences your hormones, immune system, blood sugar, inflammation, gut bacteria and even how your genes are expressed.

One of the biggest mistakes people make is thinking they need to pick one diet and stick with it forever.

Instead, think of each diet as a tool.

Just as a carpenter uses different tools for different jobs, different dietary approaches have different purposes. Some focus on reducing inflammation. Others help stabilize blood sugar. Some calm digestive symptoms, while others temporarily reduce foods that may stimulate the immune system.

Understanding why each diet exists helps you choose the one that best supports your current health goals.

Let’s take a closer look.

Mediterranean Diet

Primary functional nutrition goal: Improve blood sugar regulation and reduce insulin resistance.

Best for:

• Prediabetes
• Type 2 diabetes
• Heart disease
• Healthy aging
• Brain health
• Chronic inflammation

The Mediterranean diet consistently ranks among the healthiest eating patterns in the world. Rather than focusing on strict rules, it emphasizes eating real, minimally processed foods while enjoying meals as part of a healthy lifestyle.

Foods Included

• Vegetables: Colourful, seasonal, abundant (aim for 6–9 servings daily)
• Fruits: Whole fruits, especially berries, citrus and olives
• Fats: Extra virgin olive oil (primary fat), nuts, seeds
• Protein: Fish and seafood (2–3 times/week), legumes, moderate poultry
• Grains: Whole grains like barley, oats, farro, bulgur
• Dairy: Moderate amounts of yogurt, kefir and cheese (preferably fermented)
• Herbs and spices: Garlic, oregano, rosemary, basil, turmeric
• Limited: Red meat (1–2 times/month), processed foods, refined sugars

Why it works

This eating pattern naturally provides fibre, healthy fats, antioxidants and polyphenols that improve insulin sensitivity and reduce chronic inflammation.

Blood sugar control: The Mediterranean diet’s high fibre content (30–40g/day from vegetables, legumes and whole grains) slows glucose absorption, reduces postprandial spikes and improves insulin sensitivity. Monounsaturated fats from olive oil enhance insulin receptor function and reduce hepatic glucose production.

Inflammation reduction: Polyphenols from olive oil, nuts, red wine (in moderation) and colourful produce activate anti-inflammatory pathways, inhibit nuclear factor kappa-light-chain-enhancer of activated B cells signaling and reduce pro-inflammatory cytokines like TNF-alpha and IL-6.

Gut microbiome support: Adherence to the Mediterranean diet leads to significantly higher levels of total short-chain fatty acids (SCFAs), important gut microbiota metabolites that modulate immune–endocrine processes and improve gut barrier integrity. The diet increases beneficial taxa like Bifidobacterium, Lactobacillus and butyrate-producing species, which are linked to favorable cardiometabolic profiles.

Cardiometabolic benefits: Clinical trials show the Mediterranean diet can halve metabolic syndrome prevalence ( about 52 per cent reduction) in as little as six months, while improving lipid profiles, blood pressure and glycemic control.

I often consider the Mediterranean diet one of the best long-term nutrition strategies because it nourishes the body rather than restricting it. Once underlying digestive or immune issues have been addressed, many people can transition to this style of eating for life. Its emphasis on plant diversity, healthy fats and minimally processed foods aligns closely with precision nutrition principles that prioritize microbiome health and metabolic flexibility.

Rainbow Diet

Primary functional nutrition goal: Increase phytonutrients, flavonoids and antioxidant diversity.

Best for:

• Healthy aging
• Immune support
• Disease prevention
• Gut microbiome health
• General wellness

The Rainbow Diet focuses on eating a wide variety of colourful fruits and vegetables—aiming for at least five to nine servings daily across the full colour spectrum. Every colour contains unique plant compounds called phytonutrients, each with different benefits:

The Colour Code

Red foods (lycopene, ellagic acid):

• Tomatoes, watermelon, red peppers, strawberries, pomegranates
• Benefits: Cardiovascular protection, prostate health, antioxidant support

Orange/yellow foods (beta-carotene, vitamin C, flavonoids):

• Carrots, sweet potatoes, citrus, mangoes, turmeric
• Benefits: Immune function, eye health, skin protection

Green foods (sulforaphane, chlorophyll, lutein, folate):

• Leafy greens, broccoli, Brussels sprouts, kiwi, green tea
• Benefits: Detoxification support, cancer prevention, bone health

Blue/purple foods (anthocyanins, resveratrol):

• Blueberries, blackberries, eggplant, purple cabbage, red grapes
• Benefits: Brain health, anti-aging, vascular protection

White/tan foods (allicin, quercetin, kaempferol):

• Garlic, onions, mushrooms, cauliflower, white beans
• Benefits: Immune modulation, antimicrobial activity, cardiovascular support

The greater the diversity of plants you eat, the greater the diversity of your gut microbiome—and a healthier microbiome supports digestion, immunity, hormone balance and healthy aging. Research shows that diets rich in plant-based foods and fermentable fibers increase microbial diversity and the abundance of short-chain fatty acid–producing species, which are linked to favorable cardiometabolic profiles.

Superfood Diet

Primary functional nutrition goal: Increase antioxidant and nutrient density.

Rather than eliminating foods, the Superfood Diet encourages regularly eating foods that provide exceptionally high concentrations of vitamins, minerals and protective plant compounds.

What makes a food a “superfood”?

Superfoods are nutrient powerhouses that pack large amounts of vitamins, minerals, antioxidants, healthy fats or other bioactive compounds into relatively few calories.

Examples include:

Berries (blueberries, blackberries, raspberries, goji berries):

• High in anthocyanins, vitamin C, fibre
• Support brain health, reduce oxidative stress

Leafy greens (kale, spinach, arugula, Swiss chard):

• Rich in folate, vitamin K, magnesium, lutein
• Support detoxification, bone health, eye health

Broccoli sprouts:

• Contain 10 to 100 times more sulforaphane than mature broccoli
• Potent activators of Nrf2 detoxification pathways

Turmeric (with black pepper):

• Curcumin modulates inflammation, supports joint and brain health
• Piperine enhances curcumin absorption by 2000 per cent

Green tea (especially matcha):

• EGCG and other catechins support metabolism, brain function and cardiovascular health

Garlic (crushed and rested 10 minutes before cooking):

• Allicin formation supports immune function and cardiovascular health

Wild salmon:

• Omega-3 fatty acids (EPA/DHA) reduce inflammation, support brain and heart health

Walnuts:

• Alpha-linolenic acid (plant omega-3), polyphenols, melatonin
• Support cognitive function and cardiovascular health

Chia seeds:

• Fibre, omega-3s, complete protein, minerals
• Support gut health and satiety

Extra virgin olive oil:

• Monounsaturated fats, polyphenols (oleocanthal, oleuropein)
• Anti-inflammatory, cardioprotective

It is important to note that the term “superfood” is a marketing term, not a scientific classification. While no single food can magically reverse disease, consistently including nutrient-dense foods helps reduce oxidative stress and supports optimal cellular health. These foods are often rich in polyphenols, omega-3 fats and other bioactive compounds that modulate inflammation and support detoxification pathways.

Ketogenic Diet

Primary functional nutrition goal: Reduce insulin resistance and neuroinflammation.

Best for:

• Prediabetes
• Type 2 diabetes
• Obesity
• Certain neurological conditions
• Epilepsy
• Metabolic syndrome
• PCOS (polycystic ovary syndrome)

The ketogenic diet is a very low-carbohydrate, high-fat eating pattern that shifts the body into nutritional ketosis. Instead of using glucose as its primary fuel, the body begins producing ketones from fat.

Macronutrient breakdown

• Fat: 70 to 80 per cent of calories
• Protein: 20 to 25 per cent of calories (moderate, not high)
• Carbohydrates: Five to 10 per cent of calories (typically 20–50g net carbs/day)

Foods Included

• Proteins: Meat, fish, eggs, shellfish
• Fats: Olive oil, coconut oil, avocado oil, butter, ghee
• Low-carb vegetables: Leafy greens, broccoli, cauliflower, zucchini, asparagus
• Dairy: Cheese, cream, full-fat yogurt (in moderation)
• Nuts and seeds: Almonds, walnuts, macadamias, chia, flax (in moderation)
• Avocados: Excellent source of healthy fats and fibre

Foods to Avoid

• Grains (wheat, rice, oats, barley)
• Sugar (table sugar, honey, maple syrup, agave)
• Most fruits (except small portions of berries)
• Starchy vegetables (potatoes, corn, peas)
• Legumes (beans, lentils, chickpeas)
• Processed foods, especially those with hidden carbohydrates

Why it works

Ketones as brain fuel: Ketone bodies such as beta-hydroxybutyrate and acetoacetate serve as crucial alternative energy sources during glucose deficiency. Ketones appear to be an efficient fuel source for the brain and may reduce neuroinflammation in certain neurological conditions.

Neuroprotection: Ketone bodies act as signaling molecules that directly reduce pro-inflammatory responses in the brain, suppress microglial activation and down-regulate inflammatory genes such as TNF-alpha and nuclear factor kappa-light-chain-enhancer of activated B cells. The ketogenic diet also improves insulin sensitivity, reduces oxidative stress and may enhance mitochondrial function, all of which contribute to neuroprotection.

Metabolic benefits: By drastically reducing carbohydrate intake, the ketogenic diet minimizes insulin secretion, improves insulin sensitivity and promotes fat oxidation. This can lead to significant improvements in blood sugar control, weight loss and triglyceride levels.

Anti-inflammatory effects: The ketogenic diet reduces systemic inflammation by lowering pro-inflammatory cytokines, improving gut barrier function and modulating the gut microbiome.

Ketones appear to be an efficient fuel source for the brain and may reduce neuroinflammation in certain neurological conditions, however, keto isn’t automatically healthy. Quality matters. The “dirty keto” approach (bacon, processed meats, fast food burgers without buns) may achieve ketosis but fails to provide the micronutrients, phytonutrients and fibre needed for long-term health. A “clean” or “Mediterranean keto” approach emphasizes fatty fish, olive oil, avocados, nuts, seeds and low-carb vegetables, providing both metabolic benefits and nutritional adequacy.

Important considerations: Long-term ketogenic diets may reduce microbial diversity and limit intake of polyphenols and prebiotic fibers that support gut and metabolic health. For this reason, I typically recommend keto as a short-term therapeutic tool rather than a permanent lifestyle, unless medically indicated.

Low-Carbohydrate Diet

Primary functional nutrition goal: Reduce insulin surges and improve metabolic health.

Unlike keto, low-carb eating doesn’t require ketosis. Instead, carbohydrates are simply reduced while emphasizing vegetables, lean protein and healthy fats.

Macronutrient breakdown

• Carbohydrates: 20 to 40 per cent of calories (typically 50–150g/day)
• Protein: 25 to 35 per cent of calories
• Fat: 30 to 45 per cent of calories

Foods emphasized

• Non-starchy vegetables (unlimited)
• Quality proteins (meat, fish, eggs, poultry)
• Healthy fats (olive oil, avocado, nuts, seeds)
• Low-sugar fruits (berries in moderation)
• Some starchy vegetables (sweet potatoes, squash) based on individual tolerance

Foods reduced or eliminated

• Refined grains (white bread, pasta, pastries)
• Added sugars and sweetened beverages
• Highly processed foods
• Excessive fruit intake

Why it works

Improved insulin sensitivity: Reducing carbohydrate intake decreases postprandial glucose excursions, lowers insulin demand and improves insulin receptor sensitivity.

Metabolic flexibility: Low-carb diets train the body to efficiently switch between glucose and fat as fuel sources, improving metabolic flexibility and reducing reliance on constant carbohydrate intake.

Appetite regulation: Higher protein and fat intake increases satiety hormones (PYY, GLP-1) and reduces hunger hormones (ghrelin), leading to spontaneous calorie reduction without conscious restriction.

Lipid improvements: Low-carb diets typically reduce triglycerides, increase HDL cholesterol and shift LDL particle size toward less atherogenic patterns.

For many people, reducing refined carbohydrates is enough to improve:

• Blood sugar
• Energy
• Weight
• Cravings
• Triglycerides

Often, this approach is easier to maintain long-term than strict keto. Low-carbohydrate patterns can reduce postprandial glucose excursions, improve insulin sensitivity and support weight management without the need for sustained ketosis.

Vegetarian & vegan diets

Primary functional nutrition goal: Increase intake of plant foods and phytonutrients.

Plant-based diets naturally increase:

• Fibre
• Antioxidants
• Vitamins
• Minerals
• Polyphenols

Foods emphasized

• Vegetables: All types, especially leafy greens and colourful varieties
• Fruits: Whole fruits, especially berries and citrus
• Whole grains: Quinoa, brown rice, oats, barley, buckwheat
• Legumes: Beans, lentils, chickpeas, peas
• Nuts and seeds: Almonds, walnuts, chia, flax, hemp
• Plant proteins: Tofu, tempeh, edamame, seitan (for non-gluten-sensitive individuals)

Whole-food vegetarian and vegan diets may improve cardiovascular health and lower inflammation. However, they require careful planning to ensure adequate intake of vitamin B12, iron, zinc, iodine, vitamin D, omega-3 fats and high-quality protein. The healthiest vegan diet is one based on whole foods—not ultra-processed meat substitutes.

Gluten-free diet

Primary functional nutrition goal: Reduce dietary proteins that may stimulate the immune system in susceptible individuals. For people with celiac disease, lifelong gluten avoidance is essential. Others may be gluten sensitive and experience digestive symptoms, fatigue, headaches or joint pain that improve when gluten is removed.

Foods to avoid

• Wheat (bread, pasta, cereals, baked goods)
• Barley (beer, malt, some soups)
• Rye (rye bread, some cereals)
• Cross-contaminated oats (unless certified gluten-free)
• Processed foods with hidden gluten (soy sauce, salad dressings, processed meats)

Foods that are naturally gluten-free

• Rice, quinoa, buckwheat, millet, amaranth
• Corn, potatoes, sweet potatoes
• Fresh fruits and vegetables
• Meat, fish, eggs, dairy (unflavored)
• Legumes, nuts, seeds

Not everyone needs to avoid gluten. However, when someone has autoimmune disease, digestive symptoms or suspected gluten sensitivity, a structured elimination trial may provide valuable information. The goal is personalization—not unnecessary restriction. If you suspect gluten sensitivity, I recommend a strict four to six-week gluten elimination followed by a deliberate reintroduction challenge. Track symptoms carefully (digestive, neurological, joint pain, fatigue, skin). If symptoms clearly recur, gluten may be a trigger worth avoiding long-term. If no change occurs, gluten is likely not a primary driver of your symptoms.

Important: Never start a gluten-free diet before testing for celiac disease, as this can lead to false-negative results. If you suspect celiac disease, be sure to seek testing from your primary healthcare provider.

Gluten & dairy-free diet

Primary functional nutrition goal: Further reduce immune activation while identifying potential food sensitivities.

Removing both gluten and dairy is one of the most common short-term elimination strategies used in functional nutrition.

Why these two?

Gluten and dairy are among the most common food triggers for several reasons:

• High protein content: Both contain proteins (gluten, casein, whey) that can stimulate immune responses in susceptible individuals.
• Molecular mimicry: Some research suggests gluten and dairy proteins may share structural similarities with human tissues, potentially triggering autoimmune responses via molecular mimicry.
• Gut barrier effects: Both can increase intestinal permeability (“leaky gut”) in sensitive individuals, contributing to systemic inflammation.

Foods removed

• All gluten-containing grains (wheat, barley, rye)
• All dairy products (milk, cheese, yogurt, butter, cream)
• Processed foods containing gluten or dairy derivatives

Foods emphasized

• Vegetables, fruits, legumes
• Gluten-free grains (rice, quinoa, buckwheat, millet)
• Meat, fish, eggs
• Nuts, seeds, coconut products
• Dairy alternatives (almond milk, coconut yogurt, cashew cheese)

Upon eliminating gluten and dairy products, many individuals report improvements in:

• Bloating
• Eczema
• Sinus congestion
• Joint discomfort
• Digestive symptoms
• Fatigue and brain fog

The goal is not lifelong avoidance unless medically necessary, but rather identifying whether these foods contribute to symptoms. I often recommend a four- to six-week gluten- and dairy-free elimination as a first-line therapeutic diet for patients with autoimmune conditions, chronic inflammation or persistent digestive symptoms. If symptoms improve, systematic reintroduction (one food group at a time, over 3 days) helps identify specific triggers.

Paleo diet

Primary functional nutrition goal: Reduce dietary proteins and processed foods that may contribute to immune activation.

Foods emphasized:

• Vegetables: All types, especially non-starchy varieties
• Fruits: Whole fruits, especially berries
• Meat: Grass-fed, pasture-raised when possible
• Fish: Wild-caught, especially fatty fish
• Eggs: Pasture-raised
• Nuts and seeds: Almonds, walnuts, macadamias, chia, flax

Foods avoided:

• Grains: Wheat, rice, oats, barley, corn
• Dairy: Milk, cheese, yogurt, butter
• Legumes: Beans, lentils, chickpeas, soy
• Refined sugar: Table sugar, high-fructose corn syrup, processed sweeteners
• Processed foods: Anything with artificial ingredients, preservatives or industrial seed oils

Why it works

Eliminates processed foods: By removing refined grains, added sugars and ultra-processed foods, the Paleo diet naturally reduces exposure to inflammatory compounds, food additives and empty calories.

Increases nutrient density: Emphasis on vegetables, fruits, quality proteins and healthy fats provides abundant vitamins, minerals, antioxidants and phytonutrients.

Reduces potential immune triggers: Some individuals may benefit from removing grains, legumes and dairy, which can contain proteins (lectins, gluten, casein) that trigger immune responses in susceptible people.

Supports metabolic health: The Paleo diet’s emphasis on whole foods, healthy fats and moderate protein can improve insulin sensitivity, blood sugar control and lipid profiles.

The “strict” Paleo approach (no grains, legumes or dairy) may be beneficial short-term for those with autoimmune conditions, digestive disorders or metabolic dysfunction. However, many can eventually reintroduce well-tolerated foods like white rice, potatoes, fermented dairy or properly prepared legumes, creating a more flexible “Paleo-plus” approach that maintains metabolic benefits while increasing dietary variety and enjoyment.

Lectin-free diet

Primary functional nutrition goal: Reduce exposure to lectins in individuals who may be sensitive to them.

Lectins are naturally occurring proteins found in foods such as beans, legumes, grains, tomatoes and peppers. Some researchers believe lectins may contribute to digestive symptoms or immune activation in susceptible individuals, although evidence remains mixed.

What are lectins?

Lectins are carbohydrate-binding proteins found in many plant foods, particularly:

• Legumes: Beans, lentils, chickpeas, soybeans
• Grains: Wheat, rice, barley, oats
• Nightshades: Tomatoes, potatoes, eggplant, peppers
• Other: Peanuts, cashews, quinoa, chia seeds

Lectins are thought to contribute to digestive symptoms or immune activation in susceptible individuals by:

• Binding to intestinal cells and potentially increasing gut permeability
• Triggering immune responses in sensitive individuals
• Interfering with nutrient absorption in high amounts

Reducing Lectin Content

• Boiling beans for 15+ plus minutes reduces lectin content by up to 99 per cent
• Pressure cooking is even more effective
• Fermentation and sprouting also reduce lectins
• Lectins are concentrated in skins and seeds of nightshades, so peeling and deseeding is recommended

Most people tolerate lectin-containing foods very well, especially when properly cooked. However, selected individuals with digestive disorders or autoimmune conditions may benefit from a carefully supervised trial.

During this trial, emphasize:

• Well-cooked legumes (pressure-cooked)
• White rice over brown rice (lower lectin content)
• Peeled and deseeded nightshades
• Dairy (if tolerated) and eggs

After four to six weeks, systematically reintroduce lectin-containing foods one at a time to assess tolerance. Many individuals find they can tolerate properly prepared lectin-containing foods without issue, while others identify specific triggers worth avoiding long-term.

Nightshade-free diet

Primary functional nutrition goal: Reduce inflammatory food triggers in susceptible individuals.

Nightshade vegetables include:

• Tomatoes (all varieties, including tomato sauce, paste, ketchup)
• Potatoes (white, red, russet; sweet potatoes and yams are NOT nightshades)
• Eggplant
• Peppers (bell peppers, hot peppers, paprika, cayenne, chili powder)
• Goji berries
• Ashwagandha (an herb in the nightshade family)

Although nutritious for most people, a small percentage report worsening joint pain or autoimmune symptoms after consuming them.

Who might benefit from nightshade avoidance?

• Individuals with rheumatoid arthritis or other inflammatory joint conditions
• People with autoimmune diseases (Hashimoto’s, lupus, psoriasis)
• Those with histamine intolerance
• Individuals with inflammatory bowel disease (IBD)
• People who notice symptom flares after consuming nightshades

Rather than permanently avoiding these vegetables, I recommend using a structured elimination and reintroduction process to determine whether they are actually contributing to symptoms.

For those with autoimmune conditions or chronic joint pain, I often recommend a four to six-week nightshade-free trial as part of a broader anti-inflammatory protocol. Track symptoms carefully (joint pain, stiffness, fatigue, digestive symptoms, skin issues). If significant improvement occurs, systematically reintroduce nightshades one at a time (e.g., tomatoes for three days, then potatoes for three days, etc.) to identify specific triggers.

Autoimmune Protocol (AIP)

Primary functional nutrition goal: Significantly reduce dietary immune stimulation while promoting gut healing.

The Autoimmune Protocol removes foods commonly associated with immune activation before gradually reintroducing them.

Foods removed

• Grains: All grains (wheat, rice, oats, barley, corn, quinoa, buckwheat)
• Legumes: All beans, lentils, chickpeas, soy, peanuts
• Dairy: All dairy products (milk, cheese, yogurt, butter, cream)
• Eggs: All egg products
• Nuts and seeds: All nuts, seeds and their butters/oils (including spices derived from seeds like cumin, coriander, mustard)
• Nightshades: Tomatoes, potatoes, eggplant, peppers, paprika, cayenne
• Alcohol: All alcoholic beverages
• Processed foods: All refined sugars, food additives, artificial sweeteners, industrial seed oils
• NSAIDs: Non-steroidal anti-inflammatory drugs (ibuprofen, aspirin) are avoided during the elimination phase

Foods Emphasized

• Vegetables: Eight to 12 servings daily, focusing on variety and colour (except nightshades)
• Fruits: Two to three servings daily, especially berries
• Quality proteins: Grass-fed meat, pasture-raised poultry, wild-caught fish, organ meats
• Healthy fats: Olive oil, avocado oil, coconut oil, avocado
• Fermented foods: Coconut yogurt, sauerkraut, kimchi, kombucha (if tolerated)
• Bone broth: Rich in collagen, glycine and glutamine for gut healing
• Herbs and spices: Fresh herbs, garlic, onion, turmeric, ginger, sea salt

Why it works

Reduces immune stimulation: By removing common food triggers (gluten, dairy, eggs, nightshades, etc.), AIP significantly reduces dietary antigens that may stimulate immune responses in susceptible individuals.

Supports gut healing: Emphasis on bone broth, fermented foods, vegetables and healthy fats provides nutrients (collagen, glycine, glutamine, zinc, vitamin A) that support intestinal barrier integrity and reduce “leaky gut.”

Reduces inflammation: AIP’s focus on anti-inflammatory foods (vegetables, fruits, omega-3 fats, herbs and spices) helps lower systemic inflammation and modulate immune function.

Promotes nutrient density: By emphasizing vegetables, fruits, quality proteins and healthy fats, AIP provides abundant vitamins, minerals, antioxidants and phytonutrients that support immune regulation and overall health.

It is important to note that AIP is highly restrictive and can be challenging to follow long-term. I recommend working with a qualified practitioner to ensure nutritional adequacy, provide support and guidance through the reintroduction process. The goal is not permanent restriction, but rather identifying your unique triggers and creating a sustainable, personalized eating pattern that supports your health long-term.

Carnivore diet

Primary functional nutrition goal: Maximum elimination of plant compounds that may trigger symptoms in susceptible individuals.

The Carnivore Diet consists almost entirely of animal foods. By eliminating virtually every plant food, it removes many potential dietary triggers simultaneously.

Foods included

• Meat: Beef, pork, lamb, game (preferably grass-fed, pasture-raised)
• Fish: Salmon, sardines, mackerel, cod (wild-caught when possible)
• Poultry: Chicken, turkey, duck (pasture-raised)
• Eggs: All types (pasture-raised preferred)
• Animal fats: Tallow, lard, suet, butter, ghee
• Salt: Sea salt, Himalayan salt (to taste)
• Water: Plain water, bone broth (optional)

Foods Excluded

• All plant foods (vegetables, fruits, grains, legumes, nuts, seeds)
• All processed foods
• All added sugars and sweeteners
• All plant-based oils

Why it works

Maximum elimination: By removing all plant foods, the carnivore diet eliminates virtually every potential dietary trigger (lectins, oxalates, salicylates, histamine, FODMAPs, gluten, etc.) simultaneously.

Nutrient density: Animal foods provide highly bioavailable forms of protein, B vitamins (including B12), iron, zinc, selenium, vitamin A (retinol), vitamin D and omega-3 fats.

Simplified digestion: Removing fibre and plant compounds may reduce digestive workload and symptom triggers in individuals with severe gut dysfunction.

Metabolic effects: The carnivore diet is inherently ketogenic (very low-carb, high-fat), which may improve insulin sensitivity, reduce inflammation and support weight loss in some individuals.

Some individuals with complex autoimmune or digestive conditions report significant improvements. However, because this approach also removes fibre and thousands of beneficial phytonutrients, I generally consider it a short-term therapeutic strategy rather than a long-term lifestyle for most people. Long-term carnivore eating may reduce microbial diversity and limit intake of polyphenols and prebiotic fibers that support gut and metabolic health. I strongly recommend working with a qualified practitioner to ensure nutritional adequacy, monitoring blood work regularly (lipids, liver function, kidney function, micronutrients), and planning for eventual reintroduction of plant foods to restore microbiome diversity and phytonutrient intake.

The carnivore diet can be a powerful tool, but for most people, it’s a starting point for healing—not a permanent destination.

DASH Diet

Primary functional nutrition goal: Improve blood pressure through better mineral balance.

The DASH diet (Dietary Approaches to Stop Hypertension) emphasizes:

• Vegetables
• Fruit
• Whole grains
• Lean protein
• Low-fat dairy
• Reduced sodium
• Increased potassium
• Increased magnesium

Why it works

Blood pressure isn’t just about sodium. Adequate potassium, magnesium, fibre and overall diet quality play equally important roles in maintaining healthy blood pressure.

Sodium reduction: The DASH diet typically limits sodium to 2,300 mg/day (or 1,500 mg/day for the lower-sodium version), which can reduce systolic blood pressure by ~5–7 mmHg.

Potassium: Emphasis on fruits, vegetables and dairy provides potassium, which helps counteract sodium’s effects and relaxes blood vessel walls.

Magnesium: Whole grains, nuts, seeds and leafy greens provide magnesium, which supports vascular tone and blood pressure regulation.

Calcium: Low-fat dairy provides calcium, which may help regulate blood pressure through effects on vascular smooth muscle function.

Fibre: High fibre intake (25–30g/day) improves lipid profiles, supports healthy weight and may modestly reduce blood pressure.

The DASH diet is recommended by the National Heart, Blood, and Lung Institute to help prevent and treat metabolic syndrome, and it emphasizes eating a variety of nonstarchy vegetables, fruits, whole grains, low-fat dairy, lean meats, poultry, eggs, beans, nuts and heart-healthy fats and oils.

Low FODMAP Diet

Primary functional nutrition goal: Reduce fermentable carbohydrates that contribute to digestive symptoms.

FODMAPs are carbohydrates that can be poorly absorbed and rapidly fermented by gut bacteria. For individuals with IBS or SIBO, this often results in:

• Gas
• Bloating
• Abdominal pain
• Diarrhea and/or constipation

What are FODMAPs?

FODMAP is an acronym for Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols—short-chain carbohydrates that are poorly absorbed in the small intestine and subsequently fermented by colonic bacteria.

Oligosaccharides:

• Fructans: Wheat, rye, onions, garlic, artichokes, asparagus
• Galacto-oligosaccharides (GOS): Legumes (beans, lentils, chickpeas)

Disaccharides:

• Lactose: Milk, soft cheeses, yogurt

Monosaccharides:

• Fructose (in excess of glucose): Apples, pears, mangoes, honey, high-fructose corn syrup

Polyols:

• Sorbitol: Apples, pears, stone fruits
• Mannitol: Mushrooms, cauliflower
• Xylitol, maltitol: Sugar-free gums and candies

How FODMAPs cause symptoms

Osmotic effects: FODMAPs draw water into the small intestine, increasing luminal water content and contributing to diarrhea.

Fermentation: Gut bacteria rapidly ferment FODMAPs, producing gases (hydrogen, methane, carbon dioxide) that cause bloating, distension and abdominal pain.

Visceral hypersensitivity: In individuals with IBS, the intestinal distension from gas and water triggers heightened pain responses, leading to the characteristic symptoms of IBS.

Clinical Evidence

Randomized controlled trials demonstrate that low FODMAP diets improve abdominal bloating, pain and stool consistency in patients with IBS. In 117 recruited patients with IBS, IBS symptom severity scores improved significantly after the elimination period compared with baseline (150 ± 116 vs 301 ± 97, P < .0001, 80 per cent responders).

The low FODMAP diet reduces exposure to fermentable substrates, thereby mitigating symptom triggers.

This is a temporary therapeutic diet. The low FODMAP diet should always be followed by a structured reintroduction phase to identify specific triggers. Long-term strict low FODMAP eating can reduce beneficial gut bacteria (especially Bifidobacterium), decrease short-chain fatty acid production and compromise nutritional adequacy. Work with a qualified practitioner to ensure proper implementation, nutritional adequacy and successful reintroduction.

Low histamine diet

Primary functional nutrition goal: Reduce dietary histamine load.

Histamine-rich foods include:

• Aged cheeses (Parmesan, blue cheese, aged cheddar)
• Fermented foods (sauerkraut, kimchi, kombucha, miso, tempeh)
• Wine (especially red), beer, champagne
• Processed meats (salami, pepperoni, bacon, ham)
• Smoked fish (salmon, mackerel, sardines)
• Canned fish (tuna, sardines)
• Leftovers (histamine increases with time)
• Vinegar and vinegar-containing foods
• Soy sauce, fish sauce
• Tomatoes, eggplant, spinach
• Citrus fruits (may trigger histamine release)
• Chocolate
• Nuts (especially walnuts, cashews, peanuts)

Why some people have histamine intolerance

Histamine intolerance occurs when the body cannot break down histamine efficiently, leading to accumulation and symptoms.

Common causes:

• DAO enzyme deficiency: Diamine oxidase (DAO) is the primary enzyme that breaks down histamine in the gut. Genetic variations, gut inflammation or nutrient deficiencies (vitamin B6, copper, vitamin C) can impair DAO function.
• Gut dysbiosis: Certain gut bacteria produce histamine, while others break it down. Dysbiosis can shift this balance toward histamine accumulation.
• Mast cell activation: Some individuals have overactive mast cells that release excessive histamine in response to triggers (foods, stress, environmental factors).
• Medications: Certain medications (NSAIDs, antidepressants, antibiotics) can inhibit DAO or trigger histamine release.

Symptoms of Histamine Intolerance

• Headaches or migraines
• Flushing, redness or hives
• Itching
• Nasal congestion, runny nose
• Digestive symptoms (bloating, diarrhea, abdominal pain)
• Fatigue
• Dizziness or lightheadedness
• Heart palpitations
• Anxiety or mood changes

The goal isn’t lifelong restriction, but identifying why histamine intolerance developed, whether due to gut health, nutrient deficiencies or other underlying imbalances. After symptoms improve, systematically reintroduce histamine-containing foods to identify individual thresholds. Many individuals can eventually tolerate moderate amounts of histamine-rich foods once underlying imbalances are addressed. For a more in depth look, you can check out a previous blog post on histamine intolerance here.

Mold-Conscious (Mycotoxin) Diet

Primary functional nutrition goal: Reduce exposure to dietary mycotoxins.

Certain foods are more susceptible to mold contamination, including coffee, peanuts, corn and some grains.

What are mycotoxins?

Mycotoxins are toxic compounds produced by certain molds (fungi) that can contaminate foods, particularly in warm, humid conditions.

Common mycotoxins:

• Aflatoxins: Found in peanuts, corn, tree nuts, grains
• Ochratoxin A: Found in coffee, wine, dried fruits, grains
• Fumonisins: Found in corn and corn products
• Trichothecenes: Found in grains, especially wheat, barley, oats

Reducing mycotoxin exposure

Choose organic: Organic foods are less likely to be contaminated with mycotoxins due to stricter storage and handling requirements.

Proper storage: Store nuts, grains and spices in cool, dry conditions. Refrigerate or freeze nuts and nut butters to prevent mold growth.

Variety: Rotate your diet to avoid excessive exposure to any single potentially contaminated food.

Quality matters: Choose high-quality, reputable brands for coffee, nuts, grains and spices. Look for companies that test for mycotoxins.

Who might benefit from a mold-conscious diet?

• Individuals with chronic inflammatory response syndrome (CIRS) from mold exposure
• People with mast cell activation syndrome (MCAS)
• Those with multiple chemical sensitivities
• Individuals with autoimmune conditions and suspected environmental triggers
• People recovering from significant mold exposure (water-damaged buildings)

A mold-conscious diet is just one component of a comprehensive approach to mold-related illness. Equally important are:

• Environmental remediation: Remove yourself from moldy environments
• Binders: Use binding agents (activated charcoal, bentonite clay, chlorella) to reduce mycotoxin absorption
• Support detoxification: Support liver function with nutrients (glutathione, N-acetylcysteine, B vitamins)
• Address inflammation: Use anti-inflammatory strategies (diet, supplements, lifestyle)

Work with a qualified practitioner experienced in mold-related illness to develop a comprehensive treatment plan.

My philosophy on nutrition

After decades of helping patients improve their health, one lesson continues to stand out:

The goal isn’t to become so attached to a diet that it becomes part of your identity.

When we tie our sense of self to a particular eating pattern, we lose flexibility. We stop listening to our bodies and start defending our choices. We prioritize being “right” over feeling well.

The real goal is to understand what your body needs today.

Your nutritional needs are not fixed. They shift with your age, activity level, stress, hormones, gut health and life circumstances. A therapeutic diet that helps calm inflammation or improve blood sugar during a health challenge may no longer be necessary once your body has healed.

That’s why I believe nutrition should always be personalized—and periodically reassessed.

What served you beautifully in one chapter of your life may need adjustment in the next. Your body is constantly communicating with you through energy levels, digestion, sleep quality, mood, skin clarity and joint comfort. The art of functional nutrition lies in learning to listen.

Food isn’t simply fuel.

It is one of the most powerful forms of information we give our bodies every single day.

Yours in health,
Dr. Nathalie

Dr. Nathalie Beauchamp, B.Sc., D.C., IFMCP is the author of the book—Hack Your Health Habits: Simple, Action-Driven, Natural Solutions For People On The Go, and the creator of several online health education programs. Dr. Nathalie’s mission is to educate, lead and empower people to take control of their health. She recently launched a new book https://smartcuts.life/
For health strategies and biohacking tips sign up for her newsletter at www.drnathaliebeauchamp.com

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