mike.trainer_LA said:

I started taking a multivitamin as insurance and then found out that two of the things I was actually short of were the two it barely contains.

Vitamin D levels and micronutrients: an often-overlooked connection. Obese individuals store vitamin D in adipose tissue, making it less bioavailable. As you lose fat, vitamin D can actually increase WITHOUT supplementation.

My trajectory: Baseline 18 ng/mL → Month 6 (with supplement) 42 ng/mL → Month 12 48 ng/mL. Target is 40-60 ng/mL. Adequate vitamin D supports immune function, bone health, and mood — all relevant during weight loss.

Dr.SportsMedIN said:

Vitamin D levels and micronutrients: an often-overlooked connection.

Vitamin and mineral labs to check while on micronutrients — my doctor orders these quarterly:

• B12: Can drop due to reduced GI absorption. Mine went from 650 to 380 — now supplementing.
• Iron/Ferritin: Reduced food intake = reduced iron. Ferritin dropped from 55 to 22. Supplementing.
• Vitamin D: Was already low (18 ng/mL), now taking 5000 IU daily.
• Folate: Stable, no issues.
• Zinc: Slightly low, added a multivitamin with zinc.

Nutritional deficiencies are a real risk when you're eating significantly less. Don't skip your labs!

mike.trainer_LA said:

I started taking a multivitamin as insurance and then found out that two of the things I was actually short of were the two it barely contains.

Can confirm. Same sequence, different timescale. Posting only so the count is not one.

Clinical perspective, offered as context rather than as advice.

Iron studies on micronutrients — important especially for women:

My ferritin cratered at month 6 from reduced dietary intake. Iron bisglycinate 36mg with vitamin C brought it back up. Don't wait for anemia symptoms — test proactively.