How to Increase Free Testosterone Naturally (What the Studies Show)
If your blood test shows a normal total testosterone and you still feel flat, the number worth looking at is free testosterone. This is how to increase free testosterone using what researchers have measured in men: sleep, waist size, heavy training, vitamin D, zinc and magnesium, less beer, and pine pollen, which in a 2025 pilot study lifted free testosterone while SHBG fell.
Free vs total testosterone, and where SHBG fits
Total testosterone is everything in your blood, and most of it is bound up. Healthy Male, an Australian men's health organisation, puts free testosterone at around 2% of the total. Just under half is held by sex hormone binding globulin (SHBG), and more than half is carried on albumin.
SHBG holds testosterone tightly. Albumin lets go of it easily, which is why labs count free plus albumin-bound testosterone as "bioavailable". When SHBG climbs, more of what you make gets locked away, and free testosterone can sit low while the total looks fine. Healthy Male links high SHBG to liver disease, high thyroid hormone and some anti-seizure medicines.
How to increase free testosterone when total testosterone is normal
Normal total and low free means the problem is the bound share. Two findings point straight at it. A 2013 meta-analysis of 24 studies by Giovanni Corona and colleagues in the European Journal of Endocrinology found that weight loss raised unbound testosterone in men with obesity. And in the 2025 pine pollen pilot covered below, total testosterone barely moved while free testosterone went up and SHBG dropped by about 6%. The studies below measured testosterone more broadly, and two of them tracked free testosterone too.
How to increase free testosterone naturally
Sleep more than five hours
In 2011 Rachel Leproult and Eve Van Cauter at the University of Chicago had 10 healthy men, average age 24, sleep under five hours a night for a week. Their daytime testosterone fell by 10 to 15% (JAMA). If you're running on five hours, fix that first. It costs nothing.
Weight and waist
Corona's meta-analysis put numbers on it. A low-calorie diet raised total testosterone by an average of 2.87 nmol/L, and bariatric surgery, which takes off far more weight, by 8.73 nmol/L. Unbound testosterone rose with it. Of everything on this list, losing the gut has the biggest measured effect.
Lift heavy, rest short
William Kraemer and Nicholas Ratamess reviewed the research in Sports Medicine in 2005. Testosterone rose most after sessions that worked large muscle groups at moderate to high intensity, with plenty of volume and short rests between sets. Squats, deadlifts and rows fit that description. Low volume with long rests gave a smaller rise, and the lift showed up mostly in the 15 to 30 minutes after training.
Vitamin D
Stefan Pilz and colleagues followed 54 overweight men with low vitamin D for a year (Hormone and Metabolic Research, 2011). The 31 who took 3,332 IU of vitamin D a day went from 10.7 to 13.4 nmol/L total testosterone, and free testosterone went from 0.222 to 0.267 nmol/L.
Zinc and magnesium
Ananda Prasad's 1996 study in Nutrition gave zinc to nine older men who were marginally low in it. Six months later their serum testosterone had gone from 8.3 to 16.0 nmol/L. For magnesium, Cinar and colleagues (Biological Trace Element Research, 2011) gave 10 mg per kilogram of body weight for four weeks to tae kwon do athletes and to sedentary men. Free and total testosterone rose in both groups, more in the men who trained.
Alcohol
Four glasses of 5% beer with dinner every night for three weeks cut testosterone by 6.8% in 10 middle-aged men, compared with three weeks of non-alcoholic beer (Sierksma and colleagues, Alcoholism: Clinical and Experimental Research, 2004). A few dry nights a week is an easy trade.
Pine pollen is the pick for men who want the number to move
Pine pollen has a long head start. In 1971 Šaden-Krehula isolated testosterone, epitestosterone and androstenedione from Scots pine pollen, the first time any of them had been found in a plant. Chinese herbal texts have recorded song hua fen (松花粉) since the Tang dynasty, and it is listed in the Chinese Pharmacopoeia (2020). Our guide to pine pollen, from the Tang dynasty to the latest studies covers the full history.
Two pilot studies in men have now measured it. In 2024 Neil Wolkodoff, Gerald Haase, Robert Mordkin and Stacy Beal gave 10 men aged 47 to 78 a pine pollen tincture, half a dropper under the tongue morning and evening, for eight weeks. Average total testosterone went from 362.5 to 448.4 ng/dL. Scores on the qADAM, a questionnaire about drive, energy and erections, rose from 23.9 to 31.7 (Annals of Clinical and Medical Case Reports).
The 2025 follow-up from the same team (Haase, Wolkodoff and colleagues) looked at younger men, average age 40. In the 11 who finished the eight weeks, free testosterone rose from 10.48 to 11.72 ng/dL and SHBG fell from 29.1 to 27.4 nmol/L. Total testosterone stayed close to where it started. For a man with normal total and low free testosterone, that is the pattern he is after: more of what he already makes, unbound. Their symptom score went from 28.36 to 39.55, and the sexual function part of it from 15.27 to 20.09.
Pine Pollen – Spagyric Pine Pollen Tincture
50 ml dropper bottle. Wild-harvested, cracked-cell Pinus radiata pollen.
Add to bagWhat men notice first
Men who take pine pollen most often mention stronger morning wood and more drive by the evening. Those are the same things the qADAM asks about. Our post on pine pollen for men goes through how guys fit it around training and work.
Mara's Pine Pollen tincture
Mara's Pine Pollen is a spagyric tincture of wild-harvested, cracked-cell Pinus radiata pollen. The pollen wall is tough, so it is cracked open first. The pollen is extracted, then the minerals left behind are returned to the liquid, so the whole plant ends up in the bottle. It tastes soft and lightly earthy, with a faint sweetness.
Take 1 to 2 droppers a day. Hold it under your tongue for 20 to 30 seconds and swallow, or stir it into water or a post-workout smoothie. One dropper in the morning and one before the gym is a common rhythm, with no powder to mix and no capsules to count. The 50 ml bottle lasts 30 to 50 days. It comes in dark Miron glass. Amber glass is a step in the right direction, but Miron is the gold standard for keeping light off an extract.
Pine Pollen considerations
Contains alcohol. If you're pregnant, nursing or taking medication, ask your doctor before using it.
Questions men ask about free testosterone
Can you have normal testosterone but low free testosterone?
Yes. When SHBG is high, more of your testosterone is bound, so free testosterone can sit low while the total reads normal.
Does pine pollen lower SHBG?
In the 2025 pilot by Haase, Wolkodoff and colleagues, SHBG fell from 29.1 to 27.4 nmol/L over eight weeks in 11 men, about 6%, while free testosterone rose.
How long does it take to increase free testosterone?
Both pine pollen pilots ran for eight weeks. The zinc study ran six months and the vitamin D study a full year.
How do you take pine pollen tincture?
Take 1 to 2 droppers a day, held under the tongue for 20 to 30 seconds, or stirred into water or a smoothie.