Swapping meat for plant-based options cuts fat but lowers protein, study finds

By Vijay Kumar MalesuReviewed by Susha Cheriyedath, M.Sc.Nov 4 2025

Swapping meat for plant-based or mycoprotein products reduces saturated fat and increases fiber, but these modest changes may not significantly improve cholesterol levels and could lead to a reduction in protein intake among key age groups.

Study: The nutritional composition and impact on UK dietary intakes of meat and plant-based meat alternatives. Image Credit: barmalini / Shutterstock

In a recent study published in the journal npj Science of Food, a group of researchers quantified how like-for-like swaps of meat (ME) with plant-based meat alternatives (PBMAs) or mycoprotein (MP) in the United Kingdom (UK) affect energy and nutrient intakes across age groups using a retail nutrient database linked to the UK National Diet and Nutrition Survey (NDNS).

Rising Popularity of Plant-Based Meat Alternatives

Nearly one in three UK households now buys PBMAs at least once a year, and younger shoppers are driving much of that shift. Families want familiar meals like burgers, sausages, and nuggets without the environmental baggage of livestock. However, ME is also a key source of high-quality protein and micronutrients, such as iron, zinc, and vitamin B12, whereas many plant products add carbohydrates and sugars to mimic flavor and texture. These products are often categorized as ultra-processed foods (UPFs), which may have different nutritional and health implications compared with minimally processed meat. If a parent swaps ham for a plant-based (PB) slice, does a teen get less protein at lunch but more fiber at dinner? Clear answers matter for school menus, hospital meals, and budgets. Further research is needed to map real-world swaps to nutrient adequacy.

Building the Retail Nutrient Database

The researchers created a retail database of products available within a five-mile catchment, classifying items into ME, PB, and MP. Products were grouped into everyday categories used by UK consumers and the NDNS: bacon and ham (B&H), burgers and kebabs (B&K), chicken, turkey and dishes (CT&D), coated chicken and turkey (CC&T), and sausages (SAU). Certain meat categories, such as beef, lamb, and pork dishes, were excluded due to the lack of comparable products with PB and MP at the time of data collection. For each product, on-pack information was extracted for energy (in kilocalories), macronutrients (fat, saturated fat, carbohydrates, sugars, and protein), fiber, salt, and price per kilogram. Prices showed that PB and MP products cost approximately 38–73% more per kilogram than meat equivalents. Declared nutrient contents were then statistically compared across ingredient type and product category, with differences summarized using standard comparisons (including P-value thresholds) and multiple-comparison adjustments (e.g., Tukey’s honest significance test).

Modeling Nutrient Swaps Across Age Groups

To estimate population impact, observed ME intakes from NDNS were substituted on a like-for-like basis with PB or MP within the same product category, while holding portion patterns constant by age group. Resulting intakes were expressed as percentage contributions to Estimated Average Requirement (EAR), Dietary Reference Values (DRV), and Reference Nutrient Intake (RNI) for children (1.5–3, 4–10, 11–18 years), adults (19–64 years), and older adults (65+, including 65–74 and 75+ years). The analysis emphasized practical differences relevant to meal planning, highlighting nutrients associated with cardiometabolic risk, such as saturated fat, which affects low-density lipoprotein (LDL) cholesterol and cardiovascular disease (CVD). The authors also noted that only PBMAs, not mycoprotein, were modeled across all categories in combined analyses.

Comparing Nutritional Profiles of Meat, PBMAs, and Mycoprotein

Across the market, ME products were cheaper per kilogram than PB and MP but provided more energy, fat, saturated fat, and protein; PB and MP contained more carbohydrates, sugars (particularly PB), and fiber (with MP showing the highest fiber content). This broad pattern translated into meaningful shifts when modeled as like-for-like swaps in UK eating patterns.

Category-Specific Nutrient Differences

Bacon and Ham (B&H): ME had the highest energy, fat, saturated fat, salt, and protein, but the lowest carbohydrates, sugars, and fiber. Replacing B&H ME with PB or MP markedly lowered saturated fat contributions while raising fiber; however, protein contribution to RNI fell, especially with MP. Families aiming to cut saturated fat would benefit, but school lunch planners may need to add another protein source.

Burgers and Kebabs (B&K): ME again delivered higher energy, fat, saturated fat, and protein, while PB and MP offered more carbohydrates, sugars, fiber, and salt. Substituting ME with PB or MP reduced saturated fat intake across all age groups and substantially increased fiber, which is beneficial for teens who often under-consume fiber. The trade-off was lower protein contribution, relevant for active adolescents.

Chicken, Turkey, and Dishes (CT&D): PB versions had higher energy than ME, while MP had the lowest energy. Thus, swapping ME to MP tended to reduce energy and saturated fat, whereas swapping to PB could increase energy intake despite gains in fiber. Salt was highest in PB CT&D (1.45 g/100 g compared with 0.51 g/100 g in ME), flagging label checking for households tracking sodium. Protein remained highest in ME, with both PB and MP lowering the percentage of RNI delivered.

Coated Chicken and Turkey (CC&T): Energy levels were similar across ME, PB, and MP; however, PB and MP contained more carbohydrates, sugars, and fiber. Saturated fat was lower in PB and MP than ME, while protein favored ME. Salt tended to be lower in ME for CC&T, meaning some PB or MP options may raise sodium unless chosen carefully.

Sausages (SAU): ME had substantially higher energy, fat, saturated fat, and protein. PB and MP reduced energy and saturated fat and boosted fiber, but again at the cost of protein contribution to RNI. For older adults (65+), modeled swaps from ME to PB or MP reduced protein contribution meaningfully, potentially relevant to sarcopenia risk, suggesting menus should pair swaps with protein-dense sides (e.g., eggs, dairy, legumes) to maintain adequacy. Because plant proteins can have lower digestibility (around 80–95% compared with 95–100% for meat) and a less complete amino acid profile, pairing PBMAs with protein-dense sides can help meet higher per-meal protein targets in older adults.

Combined Nutrient Impacts of Full Meat Replacement

When all ME categories were combined and fully substituted with PBMAs, saturated fat contribution to intake dropped across age groups by approximately 2.6–3.0% of RNI, while carbohydrates and fiber rose. Protein contribution decreased consistently. Salt effects varied by category, with no consistent overall change. The authors noted that a 5–6% reduction in energy from saturated fat is usually needed to improve blood lipids, meaning these differences are likely too small to affect LDL cholesterol materially.

Balancing Fiber Gains and Protein Shortfalls

To summarize, for UK consumers, swapping ME for PBMAs or MP raises fiber and lowers saturated fat; however, the authors note that the reduction in saturated fat is likely too small to meaningfully improve blood lipids. These shifts may modestly support dietary quality goals, but are unlikely to materially change LDL cholesterol levels. Yet the gains in fiber arrive with reduced protein contribution to RNI, especially in adolescents with high needs and older adults vulnerable to sarcopenia. Additionally, the absence of micronutrient analysis (e.g., iron, zinc, B12) limits the understanding of broader dietary adequacy, and price differences may hinder household uptake. Category differences matter: some PB dishes contain more energy and salt than expected, while MP often reduces energy levels the most. Choose PBMAs and MP to boost fiber and cut saturated fat, and round out plates with protein-rich, lower-salt sides to keep meals balanced.