Meat, especially red meat, has been linked to inflammation in multiple studies. Inflammation is the body’s natural response to injury or infection. Acute inflammation helps protect and heal the body, but chronic inflammation can lead to several diseases. There are a few reasons why meat may promote inflammation in the body:
Saturated Fat
Meat contains high amounts of saturated fat. Saturated fat is a type of dietary fat that has been shown to trigger inflammatory pathways in the body. Studies show that diets high in saturated fat can increase levels of inflammatory markers like C-reactive protein (CRP) and interleukin-6 (IL-6) (1, 2). Saturated fats may also reduce levels of anti-inflammatory omega-3 fatty acids in cell membranes (3).
Advanced Glycation End Products (AGEs)
Cooking meat at high temperatures, such as grilling or frying, leads to the formation of compounds called advanced glycation end products (AGEs). AGEs form when sugars and proteins react together under high heat. They trigger oxidative stress and inflammation by binding to receptors called RAGEs (receptor for advanced glycation endproducts) (4). Higher intake of AGEs is associated with elevated levels of inflammatory markers like CRP, tumor necrosis factor alpha (TNF-α) and interleukin-6 (5).
Neu5Gc
Red meat contains a unique inflammatory compound called Neu5Gc. Humans cannot produce Neu5Gc due to a genetic mutation, but it can be absorbed into tissues from eating red meat. The immune system sees Neu5Gc as a foreign molecule and produces antibodies against it, triggering chronic inflammation (6).
Iron
Heme iron, found abundantly in red meat, has been shown to promote oxidative damage and inflammation. Iron from plant foods and supplements does not appear to have the same effect (7). Heme iron may also alter gut microbiota in a way that increases inflammation (8).
Nitrates/Nitrites
Processed meats are preserved with nitrates and nitrites. Nitrates can be converted into nitrites by bacteria in the mouth. Nitrites can then form nitrosamines, which are inflammatory compounds linked to an increased risk of certain cancers (9). Nitrites may also reduce nitric oxide, a molecule with anti-inflammatory effects (10).
Cholesterol Oxidation Products (COPs)
When cholesterol is exposed to high heat and oxygen, such as during grilling or frying, it creates cholesterol oxidation products (COPs). Studies show COPs trigger inflammatory pathways by activating immune cells and increasing inflammatory signaling molecules (11, 12).
Mechanisms Behind Meat-Induced Inflammation
There are several key mechanisms that explain how the compounds in meat trigger inflammation:
Activation of the NF-kB Pathway
The NF-kB pathway is a pro-inflammatory signaling cascade that can be activated by saturated fats, Neu5Gc antibodies, iron, nitrites and COPs (13). Activation of NF-kB leads to increased gene expression of various inflammatory cytokines, adhesion molecules and enzymes that perpetuate inflammation.
Increased Levels of Inflammatory Cytokines
Eating meat, especially processed meat, has been shown to increase levels of inflammatory cytokines like CRP, IL-6, IL-1β, TNF-α and IFN-γ (14, 15). These cytokines amplify the inflammatory response. Chronic inflammation is characterized by prolonged increased levels of inflammatory cytokines.
Oxidative Stress
Heme iron, AGEs, nitrites and COPs can all induce oxidative stress by increasing reactive oxygen species (ROS) and depleting antioxidant defenses (16). Oxidative stress activates inflammatory signaling pathways like NF-kB.
Activation of the NLRP3 Inflammasome
Saturated fats, cholesterol, palmitate and iron can activate the NLRP3 inflammasome, a protein complex that triggers the release of inflammatory cytokines (17). Activation of NLRP3 contributes to chronic inflammation in diseases like diabetes and atherosclerosis.
Altered Gut Microbiota
Meat proteins and heme iron may alter the composition of intestinal bacteria, favoring growth of bacteria that trigger inflammation (8). This change in microbiota is associated with increased intestinal permeability and higher levels of inflammatory markers.
Activation of Immune Cells
Neu5Gc antibodies activate immune cells like monocytes and macrophages, leading to the release of inflammatory molecules (6). Nitrites and COPs can also stimulate immune cells to secrete inflammatory cytokines (18, 12).
Diseases Linked to Meat-Induced Inflammation
Chronic inflammation due to high meat intake has been associated with numerous chronic diseases:
Cardiovascular Disease
Eating processed and red meat raises inflammatory markers like CRP, which directly contribute to atherosclerosis and heart disease (19). Neu5Gc antibodies may also play a role by promoting inflammation in blood vessel walls (20).
Type 2 Diabetes
Red and processed meat increase levels of inflammatory cytokines implicated in insulin resistance and diabetes progression, like IL-6 and TNF-α (21). Meat-induced inflammation may interfere with insulin signaling.
Cancer
Inflammatory compounds from meat like Neu5Gc, AGEs, nitrites and HCAs can drive tumor growth and progression. Inflammation promotes angiogenesis (new blood vessel formation) in tumors and aids in metastasis (22).
Non-Alcoholic Fatty Liver Disease
Meat-induced inflammation activates cells called Kupffer cells in the liver, triggering inflammatory cytokine production. This contributes to insulin resistance and fat accumulation in the liver (23).
Cognitive Decline
Inflammation in the brain caused by saturated fats, Neu5Gc antibodies and iron accelerates neuron damage and death. This neuroinflammation is linked to neurodegenerative diseases like Alzheimer’s (24).
| Disease | Mechanism |
|---|---|
| Cardiovascular disease | Increases CRP, IL-6, activates NF-kB |
| Type 2 diabetes | Increases IL-6, TNF-a, induces insulin resistance |
| Cancer | Promotes angiogenesis, metastasis, tumor growth |
| NAFLD | Activates Kupffer cells, increases pro-inflammatory cytokines |
| Cognitive decline | Accelerates neuron damage and death |
Ways Meat Causes Inflammation
There are several components of meat that contribute to inflammation:
Saturated Fat
- Activates NF-kB pathway
- Increases inflammatory cytokines like IL-6
- Reduces anti-inflammatory omega-3s
AGEs
- Formed when meat is cooked at high heat
- Bind to RAGE receptors and stimulate NF-kB
- Increase inflammatory cytokines
Neu5Gc
- Antibodies against Neu5Gc trigger inflammation
- Activates immune cells to release inflammatory molecules
Heme Iron
- Promotes oxidative stress
- Changes gut microbiota
- Activates NLRP3 inflammasome
Nitrates/Nitrites
- Used as preservatives in processed meats
- Form nitrosamines that are inflammatory
- May reduce nitric oxide, an anti-inflammatory molecule
COPs
- Formed when cholesterol is exposed to heat/oxygen
- Activate immune cells and increase inflammatory signaling
Reducing Inflammation from Meat
There are a few strategies to help minimize inflammation from eating meat:
Limit Red and Processed Meat
Red meats (beef, pork, lamb) and processed meats (hot dogs, bacon, sausage) tend to be most inflammatory. Poultry and fish contain less saturated fat and Neu5Gc.
Choose Grass-Fed/Pasture-Raised Meats
Grass-fed beef contains a better ratio of anti-inflammatory omega-3 to omega-6 fats compared to conventional beef (25). Pasture-raised meats also contain fewer AGEs.
Avoid Charred/Burned Meats
Charring and burning meat creates more AGEs and COPs, so cook meat at lower temperatures using gentler methods like stewing.
Marinate Meat Before Cooking
Marinades containing acidic ingredients like vinegar, lemon juice and wine help reduce AGE formation during cooking (26).
Limit Processed Meat Preservatives
Avoid processed meats with nitrates/nitrites and other chemical preservatives. Opt for uncured/preservative-free varieties.
Increase Antioxidants
Consume more antioxidants from fruits, vegetables and spices to counter oxidative damage and inflammation from meat.
Take Anti-Inflammatory Supplements
Supplements like omega-3s, curcumin, and ginger can help offset inflammation from meat.
Inflammatory Potential of Meat Types
Not all meats have the same inflammatory effects. Here is how they generally compare:
Most Inflammatory
- Processed meat (hot dogs, bacon, deli meat)
- High-fat red meat (ribeye steak, ground beef)
- Fried chicken
- Lamb
- Pork
Less Inflammatory
- Grilled chicken
- Lean cuts of beef
- Turkey
- Wild game meats
- Eggs
Least Inflammatory
- Cold water fish (salmon, cod)
- Shellfish (shrimp, mussels)
In general, seafood and poultry contain less saturated fat and Neu5Gc, while processed red meats are most inflammatory. Grass-fed, pasture-raised and organic meats also have a better fatty acid profile.
Anti-Inflammatory Dietary Swaps for Meat
To reduce meat-induced inflammation, try substituting these anti-inflammatory foods:
Protein Swaps
- Beans and legumes
- Tofu and tempeh
- Nuts and seeds
- Eggs
- Greek yogurt
Fat Swaps
- Avocado
- Olive oil
- Coconut oil
- Nut butters
Nutrient Swaps
- Leafy greens for iron
- Salmon for omega-3s
- Berries for antioxidants
- Mushrooms for vitamin D
Substituting beans, nuts, avocado and salmon can provide protein and healthy fats without the inflammatory effects of meat.
Conclusion
Meat, especially red and processed meat, contains several compounds that can trigger inflammation in the body. Saturated fat, AGEs, Neu5Gc, heme iron, nitrates/nitrites and COPs all contribute to increased inflammatory cytokines, oxidative stress, immune cell activation and altered gut bacteria. This inflammation is linked to chronic diseases like heart disease, diabetes, cancer and cognitive decline. Limiting red and processed meats, choosing grass-fed/organic meats and using gentler cooking methods can help reduce inflammation. Anti-inflammatory foods like fatty fish, beans, nuts and produce are healthier substitutes for meat.