Let $K \subset \mathbb{R}^3$ be a convex body. Assume that all orthogonal projections of $K$ onto  $2$-dimensional subspaces have a center of symmetry. Does it follow that $K$ must also have a center of symmetry?

The question that came up in some work I'm doing right now is just a bit different:

Let $K \subset \mathbb{R}^{2n}$ be a convex body. Assume all orthogonal projections of $K$ onto Lagrangian subspaces have center of symmetry. Does it follow that $K$ must also have a center of symmetry?

Note. The center of symmetry of the shadows may depend on the subspace containing it.

Theorem. If all orthogonal projections of a convex body $K \subset \mathbb{R}^n$ onto $2$-dimensional subspaces have a center of symmetry, then $K$ has a center of symmetry.

This is a classic result of Blaschke and Hessenberg (that I just learned thanks to Guillaume's comment.). A short simple proof of it can be found in Bonnesen and Fenchel.

I wonder if it is necessary to know what happens for every orthogonal projection or whether we can get by with less:

Question 1. Let $K \subset \mathbb{C}^{n}$ be a convex body. Assume all orthogonal projections of $K$ onto complex lines have a center of symmetry. Does it follow that $K$ must also have a center of symmetry?

Note. The center of symmetry of the shadows may depend on the subspace containing it.

A similar question is:

Question 2. Let $K \subset \mathbb{C}^{n}$ be a convex body. Assume all orthogonal projections of $K$ onto Lagrangian subspaces have a center of symmetry. Does it follow that $K$ must also have a center of symmetry?

Let $K \subset \mathbb{R}^3$ be a convex body. Assume that all orthogonal projections of $K$ onto $2$-dimensional subspaces have a center of symmetry. Does it follow that $K$ must also have a center of symmetry?

The question that came up in some work I'm doing right now is just a bit different:

Let $K \subset \mathbb{R}^{2n}$ be a convex body. Assume all orthogonal projections of $K$ onto Lagrangian subspaces have center of symmetry. Does it follow that $K$ must also have a center of symmetry?

Let $K \subset \mathbb{R}^3$ be a convex body. Assume that all orthogonal projections of $K$ onto $2$-dimensional subspaces have a center of symmetry. Does it follow that $K$ must also have a center of symmetry?

The question that came up in some work I'm doing right now is just a bit different:

Let $K \subset \mathbb{R}^{2n}$ be a convex body. Assume all orthogonal projections of $K$ onto Lagrangian subspaces have center of symmetry. Does it follow that $K$ must also have a center of symmetry?

Note. The center of symmetry of the shadows may depend on the subspace containing it.