Rumer Willis x Function

Brain health is personal. Knowing more can help.

Family history made brain health impossible for Rumer to ignore. Function helps bring relevant testing and whole-body context into one place.

  • Explore available brain-health add-ons, including Alzheimer’s Risk (ApoE) testing
  • See metabolic, cardiovascular, nutrient, and inflammation context together
  • Track results over time and discuss them with your clinician
Rumer Willis speaking about brain health

Family history made brain health personal

On family history, caregiving, and being proactive

Care, grief, and the choice to look closer

Loving a parent with dementia taught Rumer that grief and presence can exist together. It also made self-care and family history feel less abstract. That gave her a reason to learn what her own results could show.

Information is context, not destiny

ApoE testing can identify a genetic risk variant associated with Alzheimer’s disease. It does not diagnose Alzheimer’s or predict with certainty whether someone will develop it.

See brain health in whole-body context

Brain Health Add-ons

3 Add-On Tests
  • Alzheimer's Detection
  • Alzheimer's Risk (ApoE)
  • Brain Injury & Degeneration Screening

Heart

15 Biomarkers
  • Apolipoprotein B (ApoB)
  • HDL Cholesterol
  • HDL Large
  • High-Sensitivity C-Reactive Protein (hs-CRP)
  • LDL Cholesterol
  • LDL Medium
  • LDL Particle Number
  • LDL Pattern
  • LDL Peak Size
  • LDL Small
  • Lipoprotein(a)
  • Non-HDL Cholesterol
  • Total Cholesterol
  • Total Cholesterol/HDL Ratio
  • Triglycerides

Metabolic

5 Biomarkers
  • Glucose
  • Hemoglobin A1c (HbA1c)
  • Insulin
  • Leptin
  • Uric Acid

Nutrients

19 Biomarkers
  • Arachidonic Acid/EPA Ratio
  • Calcium
  • Ferritin
  • Homocysteine
  • Iron
  • Iron % Saturation
  • Iron Binding Capacity
  • Magnesium
  • Methylmalonic Acid (MMA/B12 Proxy)
  • Omega-3 Total
  • Omega-3: DHA
  • Omega-3: DPA
  • Omega-3: EPA
  • Omega-6/Omega-3 Ratio
  • Omega-6 Total
  • Omega-6: Arachidonic Acid
  • Omega-6: Linoleic Acid
  • Vitamin D
  • Zinc

Immune Regulation

7 Biomarkers
  • Basophils
  • Eosinophils
  • High-Sensitivity C-Reactive Protein (hs-CRP)
  • Lymphocytes
  • Monocytes
  • Neutrophils
  • White Blood Cell Count

Having suffered numerous concussions and have Alzheimers on both side of my family, Function offered me the opportunity to test my own biomarkers. Medical insurance and our health care system is broken and it would have taken me years of proving "declining" health to get access to these tests via our traditional health care system. Although the additional cost was significant, the ability to get brain specific blood tests allows me to act proactively about my health instead of waiting for decline to act when it was likely too late. That is an investment I'm willing to make and has brought me and my loved ones a sense of peace knowing where I stand now with my brain health and now to continue to monitor it. Worth every penny to able to be proactive instead of reactive.

Understanding my brain health

I've lived with this body for 57 years and what's beneath the surface has been a complete mystery to me, with the exception of standard tests ordered by doctors at various life milestones. My mother had Alzheimer's and my father had Parkinson's and while I was afraid getting tested would reveal something devastating, the 'not knowing' was starting to get to me. While my results show there are some things I need to address (Function covers them in detail), I'm very optimistic that my next round of tests in six months will show improvement, and continue to for years to come.

Facing family history, finding optimism at 57

Both of my parents suffered from Alzheimer’s and heart disease. At 40 years old I wanted insights of how I could prevent my children dealing with the same challenges. It’s also greatly reduced my medical anxiety because I don’t have as much fear of the unknown.

Reducing medical anxiety with data

Women’s health

Protecting the future starts with knowing today

Rumer wants to expand her family—and believes protecting her reproductive health means understanding it early. Function brings hormones, nutrients, inflammation, and other whole-body signals into one clear view, helping her know more now as she plans for what comes next.

  • Build a personal hormone baseline
  • Understand results alongside age, cycle timing, symptoms, and clinical guidance
  • Follow changes across life stages
Rumer Willis speaking about fertility

I’d have eight more kids if I could.

On learning more about her fertility health

Ask better questions about your body

What are my hormones telling me?

5 Biomarkers
  • Estradiol
  • FSH
  • LH
  • Prolactin
  • Sex Hormone-Binding Globulin

How is my fertility context changing?

4 Biomarkers
  • Anti-Mullerian Hormone
  • Estradiol
  • FSH
  • LH

Could my thyroid be part of the picture?

5 Biomarkers
  • Thyroid-Stimulating Hormone
  • Free T4
  • Free T3
  • Thyroid Peroxidase Antibodies
  • Thyroglobulin Antibodies

How is my metabolic health changing?

5 Biomarkers
  • Glucose
  • Hemoglobin A1c
  • Insulin
  • Apolipoprotein B
  • Triglycerides

Am I getting the nutrient context I need?

5 Biomarkers
  • Vitamin D
  • Magnesium
  • Zinc
  • Omega-3 Total
  • Homocysteine
HormonesTracking over time

Small choices. Visible change.

Rumer saw changes in her hormone results after making changes in her daily life. Her experience is personal; it does not establish that any one change caused those results.

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Rumer Willis speaking about hormone health

I didn’t expect small changes to move a hormone number.

Testimonial: Whole-body context

Advocating for myself

After years of navigating confusing symptoms and piecing together advice from different practitioners, Function gave me a clear, comprehensive view of my health in one place. It’s allowed me to connect the dots — from nutrient levels to hormones to inflammation — and finally see the whole picture instead of isolated pieces. What I appreciate most is that Function doesn’t just deliver data; it presents it in a way that’s approachable and actionable. I feel like I have a real partnership in my health now — not just lab results, but insights I can actually use to make informed decisions about my care, lifestyle, and long-term wellness. Function has helped me become a more confident advocate for myself, and I only wish I had found it sooner. ...

Testimonial: Perimenopause

Clear focus areas during perimenopause

Despite considering myself quite healthy – I maintain an active lifestyle, am lean, and follow what I believe to be a balanced diet – I was surprised to see that my bad cholesterol levels were above the normal range, and my body showed signs of elevated inflammation. The details I received from these tests were much more in-depth than what I would get at my regular doctor. I found the information incredibly valuable as it gives me clear areas to focus on for improvement. Additionally, I appreciate the inclusion of sex hormone testing, as this will be very helpful for tracking changes as I enter perimenopause. ...

Your results are connected

Brain health, hormones, thyroid, metabolism, nutrients, and cardiovascular health do not exist in isolation. Function helps you see them together and follow what changes.

160+ lab tests

Advanced testing

Advanced testing

Next steps

Clear action plans

Biological Age

Wearables

Integration with health trackers

Steps

4,787

avg

Sleep

7.5

hrs avg

Resting HR

64

bpm avg

Apple health iFit Withings Peloton Oura Fitbit Garmin

Plus, bring your results wherever you go

Share with your doctor or connect directly to AI.

Know more about your health

Build a deeper baseline and track what changes over time.

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