Animal vs Plant Protein for Menopause

Overseen By Amanda Gwin, PA-C

Age: 18+

Sex: Female

Trial Phase: Academic

Sponsor: University of Arkansas

Must not be taking: Anti-inflammatories, Metabolism-altering drugs

Disqualifiers: Musculoskeletal injuries, Metabolic diseases, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

Duration: 5 days

65 Participants Needed

Trial Summary

What is the purpose of this trial?

This will be a randomized study to determine if animal-based protein-rich food sources can stimulate greater muscle protein turnover and whole-body protein balance and reduce skeletal muscle inflammatory markers in postmenopausal women compared to vegetarian base protein-rich foods.

Will I have to stop taking my current medications?

You may need to stop taking certain medications. Specifically, you must stop using anti-inflammatory drugs for a week before and during the study, and you must suspend anti-clotting medications, including aspirin, for 5 days before a specific visit.

What data supports the effectiveness of meals consisting of plant or animal protein sources for menopause?

Research suggests that high vegetable protein intake may lower the risk of early menopause, while soy protein, a plant protein, may help with menopausal symptoms like hot flashes and maintaining bone density. Animal protein has been associated with better bone health in older women, which could be beneficial during menopause. ^{1 2 3 4 5}

Is it safe to consume animal and plant proteins during menopause?

Research suggests that both animal and plant proteins are generally safe for human consumption. Studies have shown that plant proteins may lower the risk of early menopause and animal proteins may support bone health in older adults. Soy protein, a type of plant protein, has been associated with reduced cholesterol levels and no known adverse effects in humans. ^{1 2 4 6 7}

How does the treatment of meals with plant vs. animal protein differ for menopause?

This treatment is unique because it focuses on dietary changes, specifically comparing plant-based proteins like soy, which contain isoflavones that may improve muscle and bone health, to animal-based proteins. Unlike traditional hormone replacement therapies, this approach uses food as a natural intervention to potentially manage menopause symptoms and improve body composition. ^{3 8 9 10 11}

Eligibility Criteria

This trial is for premenopausal women aged 35-45 and postmenopausal women aged 50-65 with a BMI of 20.0 - 34.9 kg/m2, who are not currently pregnant or have given birth in the past year, without metabolic or hormonal diseases, significant weight changes, or on certain medications that affect metabolism.

Inclusion Criteria

BMI of 20.0 - 34.9 kg/m2

I am a woman aged 50-65 and have not had a period for at least 12 months.

I am a woman aged 35-45 and have had regular periods for the last year.

Exclusion Criteria

I have had weight loss surgery.

I cannot stop taking my blood thinners, including aspirin, for 5 days.

My weight has changed by more than 5% in the last year.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Treatment

Participants consume either beef or isonitrogenous plant-based protein sources for 5 consecutive days

5 days

Follow-up

Participants are monitored for changes in muscle protein synthesis and inflammatory markers

1-2 weeks

Treatment Details

Interventions

• Meals consisting of plant protein sources
• Meals consisting of primarily animal protein sources

Trial Overview The study aims to compare the effects of meals rich in animal protein versus plant protein on muscle health and inflammation in pre- and postmenopausal women by randomly assigning participants to one of the two diet types.

Participant Groups

Group I: postmenopausal with obese BMI that eats vegetables as their protein source in study meals Experimental Treatment 1 Intervention

Group II: postmenopausal with obese BMI that eats primarily beef as their protein source in study meals Experimental Treatment 1 Intervention

Group III: postmenopausal with normal/overweight BMI that eats vegetables as their protein source Experimental Treatment 1 Intervention

Group IV: postmenopausal with normal/overweight BMI that eats primarily beef as their protein source Experimental Treatment 1 Intervention

Group V: premenopausal with normal/overweight BMI that eats primarily beef as their protein source Active Control 1 Intervention

Who Is Running the Clinical Trial?

University of Arkansas

Lead Sponsor

Trials

500

Recruited

153,000+

Findings from Research

In a study of 960 older adults, higher intake of animal protein was positively associated with increased bone mineral density (BMD), particularly in women, suggesting it may help protect against osteoporosis.

Conversely, higher vegetable protein intake was negatively associated with BMD in both men and women, indicating that not all protein sources have the same effects on bone health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Protein consumption and bone mineral density in the elderly : the Rancho Bernardo Study. Promislow, JH., Goodman-Gruen, D., Slymen, DJ., et al.[2019]

In a study of 85,682 premenopausal women followed from 1991 to 2011, high intake of vegetable protein was linked to a 16% lower risk of early menopause compared to low intake, suggesting a protective effect of vegetable protein on reproductive health.

Specific foods like pasta, dark bread, and cold cereal were associated with a reduced risk of early menopause, while animal protein intake showed no relationship with this risk.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary Protein Intake and Early Menopause in the Nurses' Health Study II. Boutot, ME., Purdue-Smithe, A., Whitcomb, BW., et al.[2019]

Soybeans are a complete protein source that can lower cholesterol levels and may help reduce the risk of certain cancers, particularly in populations with high soy and low animal protein diets.

Dietary whole soy protein is well tolerated and beneficial for health, but refined soy isoflavone supplements do not provide the same positive effects, and more research is needed for recommendations regarding soy intake in women with a history of breast cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Soy: a complete source of protein. Michelfelder, AJ.[2018]

In a 20-year study of 1,139 older adults, higher intake of animal protein was linked to lower all-cause and cardiovascular mortality, suggesting it may have protective health benefits for this age group.

Plant protein intake did not show a direct association with mortality outcomes, but its effects varied based on the presence of hypertension, indicating that individual health conditions may influence dietary impacts.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Animal Protein Intake Is Inversely Associated With Mortality in Older Adults: The InCHIANTI Study. Meroño, T., Zamora-Ros, R., Hidalgo-Liberona, N., et al.[2022]

Combining both plant and animal protein with physical activity is most effective for improving bone health and reducing fall risk, while high protein intake can be harmful during periods of inactivity, such as bed rest.

Plant protein, despite containing isoflavones, does not provide greater benefits for bone health compared to animal protein, and can even lead to increased bone resorption, highlighting the importance of a balanced diet for maintaining bone density, especially in older adults.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Impact of Dietary Protein on Osteoporosis Development. Kędzia, G., Woźniak, M., Samborski, W., et al.[2023]

A daily intake of 25 g of soy protein can significantly lower total cholesterol and LDL cholesterol levels, contributing to a reduced risk of coronary heart disease, as supported by various studies.

Soy isoflavones may have protective effects on breast tissue and do not show adverse effects in humans, but more randomized clinical trials are needed to confirm their role in hormone replacement therapy and other health benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Soy isoflavones: are they useful in menopause? Vincent, A., Fitzpatrick, LA.[2023]

Canadian adults who consumed more than 50% of their protein from plant sources had higher intakes of beneficial nutrients like dietary fiber, folate, iron, and magnesium, but lower intakes of total and saturated fat, vitamin D, and vitamin B12.

A balanced diet that includes both plant and animal protein sources leads to better overall nutrient quality compared to diets that are heavily focused on either animal or plant proteins.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

An examination of contributions of animal- and plant-based dietary patterns on the nutrient quality of diets of adult Canadians. Fabek, H., Sanchez-Hernandez, D., Ahmed, M., et al.[2022]

Soy foods, rich in protein and isoflavones, have been shown to improve muscle and bone density in postmenopausal women, which is crucial for preventing conditions like osteosarcopenia.

Incorporating soy into the diet can also help reduce body weight, making it a beneficial dietary choice for managing body composition changes associated with menopause.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of Soy Foods in Postmenopausal Women: A Focus on Osteosarcopenia and Obesity. Tang, S., Du, Y., Oh, C., et al.[2020]

In a study of 10,977 US adults, it was found that 46% of protein intake came from animal sources, 16% from dairy, and 30% from plant sources, highlighting the current distribution of protein consumption in the American diet.

The primary sources of protein were identified as chicken and beef for animal protein, cheese and reduced-fat milk for dairy, and yeast breads and nuts for plant protein, providing a baseline for future public health interventions aimed at improving protein quality in diets.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sources and Amounts of Animal, Dairy, and Plant Protein Intake of US Adults in 2007-2010. Pasiakos, SM., Agarwal, S., Lieberman, HR., et al.[2018]

In a study of 15 healthy premenopausal women over 9 months, consuming 60 g of textured vegetable protein (TVP) with 45 mg of conjugated isoflavones significantly increased the length of the follicular phase and delayed peak progesterone concentrations.

The intake of 45 mg of conjugated isoflavones also suppressed mid-cycle peaks of luteinizing hormone (LH) and follicle stimulating hormone (FSH), while a significant reduction in total cholesterol was observed, indicating potential hormonal and cardiovascular benefits from isoflavone consumption.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Biological effects of isoflavones in young women: importance of the chemical composition of soyabean products. Cassidy, A., Bingham, S., Setchell, K.[2023]

In a one-year study involving 87 postmenopausal women, daily consumption of soy protein (25 g) and isoflavones did not prevent bone loss in the lumbar region and whole body, despite positive effects on markers of bone formation.

Both soy and control groups showed increased levels of bone formation markers, but neither treatment affected bone resorption, indicating that while soy may support bone health, it does not stop the decline in bone density in postmenopausal women.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

One year soy protein supplementation has positive effects on bone formation markers but not bone density in postmenopausal women. Arjmandi, BH., Lucas, EA., Khalil, DA., et al.[2022]

References

1. United States pubmed.ncbi.nlm.nih.gov

Protein consumption and bone mineral density in the elderly : the Rancho Bernardo Study. [2019]

2. United States pubmed.ncbi.nlm.nih.gov

Dietary Protein Intake and Early Menopause in the Nurses' Health Study II. [2019]

3. United States pubmed.ncbi.nlm.nih.gov

Soy: a complete source of protein. [2018]

4. United States pubmed.ncbi.nlm.nih.gov

Animal Protein Intake Is Inversely Associated With Mortality in Older Adults: The InCHIANTI Study. [2022]

5. Switzerland pubmed.ncbi.nlm.nih.gov

Impact of Dietary Protein on Osteoporosis Development. [2023]

6. England pubmed.ncbi.nlm.nih.gov

Soy isoflavones: are they useful in menopause? [2023]

7. Canada pubmed.ncbi.nlm.nih.gov

An examination of contributions of animal- and plant-based dietary patterns on the nutrient quality of diets of adult Canadians. [2022]

8. Korea (South) pubmed.ncbi.nlm.nih.gov

Effects of Soy Foods in Postmenopausal Women: A Focus on Osteosarcopenia and Obesity. [2020]

9. Switzerland pubmed.ncbi.nlm.nih.gov

Sources and Amounts of Animal, Dairy, and Plant Protein Intake of US Adults in 2007-2010. [2018]

10. England pubmed.ncbi.nlm.nih.gov

Biological effects of isoflavones in young women: importance of the chemical composition of soyabean products. [2023]

11. England pubmed.ncbi.nlm.nih.gov

One year soy protein supplementation has positive effects on bone formation markers but not bone density in postmenopausal women. [2022]