Being the trouble maker that I am, I had a thought while watching TV with my family. Could the researchers have it wrong? Could it be something besides (or in addition to) the Bergamottin in the grapefruit juice that it increasing the absorption of the CoQ10.
Take all the following into consideration (backed-up by below studies):
1) The Japanese Study found Dole Grapefruit Juice increased absorption of CoQ10.
2) All Dole Juices are and have always been pasteurized.
3) Pasteurizing grapefruit juice decreases bergamottin to the point where it no longer increases the absorption of some drugs.
Therefore, it’s likely that it’s something beyond bergamottin in the grapefruit juice that is increasing the absorption of CoQ10. If that’s the case, then it must be something that is not significantly decreased when pasteurizing the grapefruit juice. Time for the researchers to do more studies.
Backup
In the Japanese Study, they found that “In the presence of GFJ, the basal-to-apical transport of CoQ10 was decreased and the uptake of CoQ10 was increased. These findings suggest that the combined administration of CoQ10 and GFJ could enhance CoQ10 absorption.”
https://www.sciencedirect.com/science/article/pii/S030881460901245X
In that study, they used Dole Grapefruit Juice. Dole’s own corporate website states that “All DOLE Canned Juices have always been pasteurized and are commercially sterile.”
https://dolesunshine.com/company-info/faq/juices
Yet, the studies on grapefruit juice when it is pasteurized show that Bergamottin is decreased to the point where it no longer impacts the increased absorption of some medications.
Study: “Grapefruit juice (GJ) contains components that may increase the bioavailability of drugs; however, approaches to the removal of these components have been little investigated. It is known that furanocoumarin derivatives (FCs), such as
bergamottin (BG) and 6′,7′-dihydroxybergamottin (DHB) in GJ, induce such drug interactions.
In the present study, it was found that the heat treatment of grapefruit juice decreases concentrations of BG and DHB as well as their interactions both in vitro and in vivo. We incubated GJ for 10, 20, 30, 40, 50, and 60 min at 37, 62, 72, and 95 °C; FCs in each sample were then measured, using high-performance liquid chromatography (HPLC).
The concentrations of BG and DHB were decreased in a time- and temperature-dependent manner, by 82.5 and 97.9% respectively, after incubation for 1 h at 95 °C. In contrast, the concentration of bergaptrol (BT) increased in a time- and temperature-dependent manner (27.7% after 60 min at 95 °C). In addition, the effect of each GJ sample on testosterone 6β-oxidation in human liver microsomes was observed. The inhibitory effects of GJ heated to 95 °C were decreased in a time-dependent manner, as in the case of BG and DHB concentrations. Furthermore, 2 ml of GJ treated for 60 min at 95 °C was administered into the rat duodenum. After 30 min, nifedipine (NFP) was administered intraduodenally at a dose of 3 mg/kg body weight. The concentrations of NFP in the plasma samples were determined by HPLC. No significant increase in the AUC of NFP was observed in the rats given heat-treated GJ. These results suggest that the heat treatment of GJ reduces the concentrations of FCs, thus eliminating the potential for drug interactions.”
https://www.jstage.jst.go.jp/article/bpb/29/11/29_11_2274/_article/-char/ja/
Study Title “A furanocoumarin-free grapefruit juice establishes furanocoumarins as the mediators of the grapefruit juice–felodipine interaction1–3”
Objective: To ascertain whether furanocoumarins mediate the GFJfelodipine interaction, a furanocoumarin-free GFJ was created and tested against orange juice and the original GFJ with respect to the oral pharmacokinetics of felodipine.
Design: With the use of food-grade solvents and absorption resins, furanocoumarins were removed (99%) from whole GFJ, whereas other major ingredients (flavonoids) were retained. In an open, 3-way, randomized crossover design, 18 healthy volunteers ingested felodipine (10 mg) with 1 of the 3 juices (240 mL). Blood was collected over 24 h. At least 1 wk elapsed between juice treatments.
Results: The median and range of the area under the curve and the maximum concentration of felodipine were significantly (P 0.001) greater with consumption of GFJ [110 (range: 58 –270) nmol · h/L and 21 (7.6 –50) nmol/L, respectively] than with that of orange juice [54 (29 –150) nmol · h/L and 7.6 (3.4 –13.9) nmol/L, respectively] or furanocoumarin-free GFJ [48 (23–120) nmol · h/L and 8.3 (3.0 –16.6) nmol/L, respectively]. GFJ, orange juice, and furanocoumarin-free GFJ did not differ significantly (P 0.09) in median time to reach maximum plasma concentration [2.5 (1.5– 6), 2.8 (1.5– 4), and 2.5 (2– 6) h, respectively] or terminal half-life [6.6 (4.2–13.6), 7.8 (4.4 –13.2), and 6.8 (2.6 –14.4) h, respectively].
Conclusion: Furanocoumarins are the active ingredients in GFJ responsible for enhancing the systemic exposure of felodipine and probably other CYP3A4 substrates that undergo extensive intestinal first-pass metabolism. Am J Clin Nutr 2006;83:1097–105.”
https://academic.oup.com/ajcn/article-pdf/83/5/1097/23889213/znu00506001097.pdf
The immediate above study created their furanocoumarin-free grapefruit juice by:
“To facilitate the administration of the original and FC-free GFJ for clinical testing, each juice was
pasteurized at 195 °F for 8 s and cold-filled in 300-mL portions into labeled 480-mL glass bottles by using a Microthermics Model 25 pasteurizer (Raleigh, NC).”
That’s a much shorter time (8 seconds at 195 degrees) of pasteurizing than the amount of time in the study immediately above it (1 hour at 95 degrees). Wikipedia states that flash pasteurization happens when “The liquid moves in a controlled, continuous flow while subjected to temperatures of 71.5 °C (160 °F) to 74 °C (165 °F), for about 15 to 30 seconds.’ So this second study is closer to flash pasteurization than the first study. All three brands of the grapefruit juice I have been drinking have been labeled pasteurized. The Wegmans brand was labeled “Flash Pasteurized”.
I may have had a little more energy on the grapefruit over the grapefruit juice. A few of my notes make me think this is the case by my energy diary. Yet it is subjective. But if grapefruit is impacting estrogen and bergamottin, whereas pasteurized grapefruit juice is not, then that could account for the slight difference.
Of course, don’t lose site that the Japanese study at the top found that Dole Grapefruit Juice increased absorption of CoQ10, so don’t throw out that grapefruit juice. I just want to help out any researcher who is trying to pinpoint what the various ingredients might be that might go into a future medication. If the best med would be bergamottin plus something else, then I’d like them to figure that out.
There were signs that the grapefruit was impacting my estrogen in my body. For example, in the month that I was eating grapefruit every day, the time between my cycles increased by two days and it was significantly heavier and my face was full of a lot more acne (including hormonal acne along the chin line). Neither of the two first things has happened in years. For the last few years, as I’m approaching menopause, the time between cycles is decreasing and it is significantly lighter (except for the month on grapefruit). My acne and face is back to my normal amount of acne (not the crazy amount I had on grapefruit). With the concern that grapefruit (not grapefruit juice) increased estrogen and the possibility of increased risk for breast cancer, my self-test showed for me that grapefruit (not grapefruit juice) impacts my estrogen. I’m still sticking with grapefruit juice for now.
